U.S. patent application number 16/305784 was filed with the patent office on 2020-07-23 for a cosmetic substrate and a cosmetic containing the cosmetic substrate.
This patent application is currently assigned to SEIWA KASEI COMPANY, LIMITED. The applicant listed for this patent is SEIWA KASEI COMPANY, LIMITED. Invention is credited to Yuta HOMMA, Shota TOMIHISA, Masato YOSHIOKA.
Application Number | 20200230034 16/305784 |
Document ID | / |
Family ID | 60477750 |
Filed Date | 2020-07-23 |
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United States Patent
Application |
20200230034 |
Kind Code |
A1 |
YOSHIOKA; Masato ; et
al. |
July 23, 2020 |
A COSMETIC SUBSTRATE AND A COSMETIC CONTAINING THE COSMETIC
SUBSTRATE
Abstract
Microcapsules are produced by forming a wall membrane by the
co-polycondensation of a silylated amino acid with a silane
compound at an interface between an oily phase and an aqueous phase
in an emulsified state and using a dispersed phase of either the
oily phase or the aqueous phase as a content encapsulated therein.
Provided are: the microcapsules thus produced which are to be used
in cosmetics, quasi drugs and drugs, said microcapsules being
capable of containing the content encapsulated therein at a high
content ratio, showing little leaching out of the content with the
lapse of time, showing little odor derived from the capsule wall
membrane, exhibiting high storage stability without aggregation or
sedimentation when used in cosmetics, and being easy to produce;
and a cosmetic comprising the same.
Inventors: |
YOSHIOKA; Masato;
(Higashiosaka-shi, JP) ; TOMIHISA; Shota;
(Higashiosaka-shi, JP) ; HOMMA; Yuta;
(Higashiosaka-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SEIWA KASEI COMPANY, LIMITED |
Osaka |
|
JP |
|
|
Assignee: |
SEIWA KASEI COMPANY,
LIMITED
Higashiosaka-shi, Osaka
JP
|
Family ID: |
60477750 |
Appl. No.: |
16/305784 |
Filed: |
May 17, 2017 |
PCT Filed: |
May 17, 2017 |
PCT NO: |
PCT/JP2017/018585 |
371 Date: |
November 29, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61Q 1/06 20130101; A61K
8/898 20130101; A61K 2800/10 20130101; A61Q 19/00 20130101; A61K
8/891 20130101; A61K 8/11 20130101; A61Q 17/04 20130101; A61K
8/0279 20130101 |
International
Class: |
A61K 8/02 20060101
A61K008/02; A61K 8/891 20060101 A61K008/891; A61K 8/11 20060101
A61K008/11 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 3, 2016 |
JP |
2016-111895 |
Claims
1.-8. (canceled)
9. A microcapsule containing core material in which the capsule
wall is made of a silylated amino acid/silane compound copolymer
which is a copolymer having a structural unit U represented by the
following general formula (Ia), (Ib) or (Ic): ##STR00005## wherein,
R.sup.2 represents an alkyl group having 1 to 20 carbon atoms, each
R.sup.2 may be the same or different, and a structural unit W
represented by the following general formula (Id) or (Ie):
##STR00006## wherein, R.sup.1 represents an alkyl group having 1 to
3 carbon atoms, each R.sup.1 may be the same or different, A is a
divalent group connecting Si and N and is at least one group
selected from the group consisting of --CH.sub.2--,
--CH.sub.2CH.sub.2--, --CH.sub.2CH.sup.2CH.sub.2--,
*--(CH.sub.2).sub.3OCH.sub.2CH(OH)CH.sub.2-- and
*--(CH.sub.2).sub.3OCOH.sub.2CH.sub.2-- (* indicates the side that
bonds to Si), and E is a residue obtained by removing one primary
amino group from an .alpha. amino acid.
10. A microcapsule containing core material according to claim 9,
in which the structural unit U is represented by formula (Ia) or
(Ib) and the structural unit W is represented by formula (Ie).
11. A microcapsule containing core material according to claim 9,
in which the .alpha. amino acid is a hydrophilic .alpha. amino
acid.
12. A microcapsule containing core material according to claim 9,
in which a group represented by the following general formula (II)
is bonded to the end of the silylated amino acid/silane compound
copolymer; ##STR00007## wherein, R.sup.1 represents an alkyl group
having 1 to 4 carbon atoms or a phenyl group, each R.sup.3 may be
the same or different.
13. A microcapsule containing core material which has capsule wall
made of a silylated amino acid/silane compound copolymer obtained
by copolycondensing a silylated amino acid in which a group
represented by the following general formula (III): ##STR00008##
wherein, R.sup.11 represents a hydroxyl group or an alkyl group
having 1 to 3 carbon atoms, and A1 represents a connecting group
selected from a group consisting of --CH.sub.2--,
--CH.sub.2CH.sub.2--, --CH.sub.2CH.sub.2CH.sub.2--,
*--(CH.sub.2).sub.3OCH.sub.2CH(OH)CH.sub.2-- and
*--(CH.sub.2).sub.3OCOCH.sub.2CH.sub.2-- (* indicates a side that
bonds to Si), is bonded to an amino group of an alpha-amino acid
and a same compound represented by the following general formula
(IV): R.sup.21.sub.mSi(OH).sub.nY.sub.(4-n-m) (IV) wherein,
R.sup.21 represents an alkyl group having 1 to 20 carbon atoms or a
phenyl group, m is an integer from 0 to 3, all the m of R.sup.21
may be the same or different, n is an integer from 0 to 4,
m+n.ltoreq.4, (4-n-m) of Y represent a hydrogen or an alkoxy group
having 1 to 6 carbon atoms, in a dispersion in which a phase of an
oily substance to become core material is dispersed in a continuous
phase constituted of an aqueous substance, or in a dispersion in
which a phase of an aqueous substance to become core material is
dispersed in a continuous phase constituted of an oily substance;
and which contains the above-core material.
14. A microcapsule containing core material according to claim 13,
in which the continuous phase is an aqueous substance and the
dispersed phase is an oily substance.
15. A cosmetic characterized in that microcapsules containing core
material according to claim 9 are contained.
16. A cosmetic according to claim 15 characterized in that 0.01
mass % to 35 mass % of the microcapsules containing core material
are contained.
17. A microcapsule containing core material according to claim 9,
in which A in the general formula (Id) and (Ie) represents
*--(CH.sub.2).sub.3OCH.sub.2CH(OH)CH.sub.2-- (* indicates the side
that bonds to Si).
18. A microcapsule containing core material according to claim 13,
in which A1 in the general formula (III) represents
*--(CH.sub.2).sub.3OCH.sub.2CH(OH)CH.sub.2-- (* indicates a side
that bonds to Si).
Description
TECHNICAL FIELD
[0001] The present invention relates to a microcapsule containing
core material and to a cosmetic containing the microcapsules
containing core material for use in cosmetics, quasi-drugs, drugs,
etc. More particularly, the present invention relates to a
microcapsule containing core material which is easy to manufacture,
causing almost no leaching of the core material, exhibiting
extremely high stability where almost no precipitation occurs by
aggregation of the capsules, and generating almost no odor from the
capsule wall; and to a cosmetic containing the same.
BACKGROUND ART
[0002] Conventionally, microcapsules in which a drug and the like
are contained are widely used in cosmetics and in pharmaceuticals.
In the cosmetics field, for example, they have been used for the
purposes to prevent direct contact between skin and an active
ingredient which may cause inflammation in skin, by encapsulating
the ingredient into the microcapsules (Patent Document 1), and to
exert long-term effects of the component such as flavor to be
released gradually from the capsules (Patent Document 2).
[0003] As the material constituting the wall membrane of the
capsule (wall material), proteins, natural substances such as
polysaccharides, and acrylic polymers, as well as biostable
silicone materials have been used. The present inventors have
developed a microcapsule containing an oily substance such as an
ultraviolet absorber in which a co-polycondensate of silylated
peptide and silane compound was used as wall material (Patent
Documents 3 and 4). Since the microcapsule using the
co-polycondensate of silylated peptide and silane compound as wall
material has dense capsule wall, causes less leaching of core
material and is excellent in stability over time, it has been
widely used in the cosmetics field.
[0004] In the cosmetics field, in the case of encapsulation for the
purpose to prevent direct contact between skin and active
ingredient, it is necessary to construct capsule wall enough to
prevent leaching of the contained ingredient from the capsule. On
the other hand, when containing the substance such as ultraviolet
absorber, constructing excessively thick wall will deteriorate
ultraviolet absorbing ability or the like, and the absorbent will
not exert its capability sufficiently. In skin cosmetics, when the
capsule particle diameter is large, or the distribution of the
particle size of the capsule is wide, problems such as giving
foreign body feeling when applied to skin, or makeup float (white
float) may occur.
[0005] Furthermore, the use of natural polymers such as
polysaccharides, proteins and their hydrolysates as the wall
material of the capsule may cause problems such as giving sticky
feeling (stickiness) to hair and skin, depending on external
humidity, or generating odor from the wall material. Furthermore,
the microcapsules described in Patent Documents 3 and 4, which
utilize co-polycondensates of silylated peptide and silane compound
as wall material, have following problems, since the peptide
portion of the silylated peptide was derived from natural
protein.
[0006] For example, natural proteins often have an isoelectric
point at acidic pH and peptides produced by hydrolyzation of the
natural proteins are prone to aggregation and precipitation at the
pH, or aggregation by associating with cationic substances combined
in cosmetics. Remaining odor in final formulation which comes from
the raw materials or generated upon hydrolysis of proteins is also
a problem. The extent of hydrolysis of proteins must be controlled
depending on the proteins in the preparation of peptides, and the
molar ratio of silylated peptide and silane compound in the
co-polycondensation reaction must be carefully determined in
advance, making the manufacture of the microcapsules complicated.
Therefore, development of a method which solves the above problems
and makes the manufacture of microcapsules easier has been
desired.
PRIOR ART REFERENCES
Patent Documents
[0007] Patent Document 1: JP-A-2002-037713 [0008] Patent Document
2: JP-A-10-277512 [0009] Patent Document 3: JP-A-11-221459 [0010]
Patent Document 4: JP-A-2000-225332
SUMMARY OF THE INVENTION
Subjects to be Solved by the Invention
[0011] An object of the present invention is to provide a
microcapsule that contains core material causing less leaching of
the core material, generating almost no odor from wall material,
having high stability in wide pH range, and not causing aggregation
by associating with substance combined with in cosmetic
formulations, yet core materials can exhibit their activity
sufficiently.
[0012] Another object of the present invention is to provide a
cosmetic comprising the microcapsules containing core material as a
cosmetic substrate.
Means for Solving the Subjects
[0013] The present inventors have conducted extensive studies to
solve the above subjects, and, as a result, have found that; [0014]
a microcapsule containing core material such as a drug or the like,
having a wall material made of a copolymer of silylated amino acid
and silane compound which is easy to manufacture by
co-polycondensation of a silylated amino acid and a silane
compound, and the microcapsule thus manufactured has good
stability, causes almost no leaching of core material, has good
stability over time without causing aggregation and precipitation
even at low pH or in the presence of cationic substances, and
generates almost no odor from the wall material; and have completed
the present invention.
[0015] The present invention provides, as a first embodiment
thereof, [0016] a microcapsule containing core material in which
[0017] the capsule wall is made of a silylated amino acid/silane
compound copolymer which has a structural unit U represented by the
following general formula (Ia), (Ib) or (Ic):
[0017] ##STR00001## [0018] wherein, R.sup.2 represents an alkyl
group having 1 to 20 carbon atoms, each R.sup.2 may be the same or
different, and [0019] a structural unit W represented by the
following general formula (Id) or (Ie):
[0019] ##STR00002## [0020] wherein, R.sup.1 represents an alkyl
group having 1 to 3 carbon atoms, each R.sup.1 may be the same or
different, A is a divalent group connecting Si and N and is at
least one group selected from the group consisting of --CH.sub.2--,
--CH.sub.2CH.sub.2--, --CH.sub.2CH.sub.2CH.sub.2--,
*--(CH.sub.2).sub.3OCH.sub.2CH(OH) CH.sub.2-- and
*--(CH.sub.2).sub.3OCOCH.sub.2CH.sub.2-- (* indicates the side that
bonds to Si), and E is a residue obtained by removing one primary
amino group from an .alpha. amino acid (claim 1).
[0021] Note that when E represents a residue obtained by removing
one primary amino group from an .alpha. amino acid which has even
other amino group other than the .alpha.-amino group (a basic amino
acid such as lysine), the primary amino group to be removed may be
either the .alpha.-amino group or the other amino group. Further,
in this case, N of the amino group remaining in E may be bonded to
A in the other structural units W.
[0022] The present invention also provides, as preferred
embodiments of the first embodiment; [0023] a microcapsule
containing core material of the first embodiment, in which the
structural unit U is represented by formula (Ia) or (Ib) and the
structural unit W is represented by formula (Ie) (claim 2); [0024]
a microcapsule containing core material of the first embodiment, in
which the .alpha. amino acid is a hydrophilic amino acid (claim 3);
and [0025] a microcapsule containing core material of the first
embodiment, in which a group represented by the following general
formula (II) is bonded to the end of the silylated amino/silane
compound copolymer (claim 4).
##STR00003##
[0025] wherein, R.sup.3 represents an alkyl group having 1 to 4
carbon atoms or a phenyl group, each R.sup.3 may be the same or
different.
[0026] The microcapsule containing core material in which a group
represented by the general formula (II) is bonded to the end of the
silylated amino/silane compound copolymer can be produced by
performing a surface treatment of the capsule for preventing
aggregation which will be described below.
[0027] The present invention provides, as a second embodiment
thereof, [0028] a microcapsule containing core material [0029]
which has capsule wall made of a silylated amino acid/silane
compound copolymer obtained by co-polycondensation of [0030] a
silylated amino acid in which a silyl group represented by the
following general formula (III):
##STR00004##
[0031] wherein, R.sup.11 represents a hydroxyl group or an alkyl
group having 1 to 3 carbon atoms, and A1 represents a connecting
group selected from a group consisting of --CH.sub.2--,
--CH.sub.2CH.sub.2--, --CH.sub.2CH.sub.2CH.sub.2--,
*--(CH.sub.2).sub.3OCH.sub.2CH(OH)CH.sub.2-- and
*--(CH.sub.2).sub.3OCOCH.sub.2CH.sub.2-- (* indicates a side that
bonds to Si), is bonded to an amino group of an .alpha.-amino acid
and [0032] a silane compound represented by the following general
formula (IV):
[0032] R.sup.21.sub.mSi(OH).sub.nY.sub.(4-n-m) (IV)
, wherein, R.sup.21 represents an alkyl group having 1 to 20 carbon
atoms or a phenyl group, m is an integer from 0 to 3, all the m of
R.sup.21 may be the same or different, n is an integer from 0 to 4,
m+n.ltoreq.4, (4-n-m) of Y represent a hydrogen or an alkoxy group
having 1 to 6 carbon atoms, [0033] in a dispersion in which a phase
of an oily substance to become core material is dispersing in a
continuous phase constituted of an aqueous substance, or [0034] in
a dispersion in which a phase of an aqueous substance to become
core material is dispersing in a continuous phase constituted of an
oily substance; and [0035] which contains the above-core material
(claim 5).
[0036] In the general formula (IV), n is preferably an integer from
2 to 4.
[0037] The microcapsule containing core material of the first
embodiment can be prepared by the same procedure as the
microcapsule containing core material of the second embodiment.
That is, the microcapsule containing core material of the second
embodiment is a microcapsule containing core material of the first
embodiment defined by its manufacturing process.
[0038] In the co-polycondensation, the silylated amino acid in
which a silyl group represented by the general formula (III) is
bonded is used in an amount of 0.1 to 40 times molar amounts
preferably, more preferably 1 to 20 times molar amounts, of the
silane compound represented by formula (IV).
[0039] In the co-polycondensation of the silylated amino acid and
the silane compound represented by general formula (IV) for
manufacturing microcapsules containing core material of the second
embodiment, the capsule walls are formed at the interface between
the continuous phase and the dispersed phase in the dispersion and
microcapsules containing the dispersed phase as the core material
are generated. Therefore, when the raw material for capsule wall is
a compound having a hydrophilic portion and a hydrophobic portion,
the co-polycondensation at the interface tends to occur easily, and
microcapsules having higher stability can be obtained. Therefore,
as an .alpha. amino acid used for a raw material of the silylated
amino acid, a hydrophilic amino acid is preferred.
[0040] In both when the continuous phase is an aqueous substance
and the dispersed phase is an oily substance, and when the
continuous phase is an oily substance and the dispersed phase is an
aqueous substance, a microcapsule containing core material of the
present invention can be formed, although the microcapsule
containing therein an oily material will have stronger capsule wall
and cause leaching of core material much less than the microcapsule
containing therein an aqueous material. Thus, as a preferred
embodiment of the second embodiment, a microcapsule containing core
material in which the continuous phase is an aqueous substance and
the dispersed phase is an oily substance is provided (claim 6).
[0041] The present invention provides a cosmetic characterized in
that the microcapsules containing core material of the first
embodiment or the second embodiment are contained (claim 7) as the
third embodiment. By blending the microcapsules containing core
material of the first embodiment or the second embodiment in the
cosmetic, the core material in the micro capsules can exert its
effect on hair or skin and the like.
[0042] Although preferred range of content of microcapsules
containing core material of the first embodiment or the second
embodiment in a cosmetic of the third embodiment varies depending
on the type and form of cosmetic and the type of core material, the
range of 0.01 mass % to 35 mass % in cosmetic is often preferred to
make the core material exert its effect sufficiently. Thus, as a
preferred embodiment of the third embodiment, a cosmetic containing
0.01 mass % to 35 mass % of the microcapsules containing core
material described above is provided (claim 8).
Effect of the Invention
[0043] The microcapsule containing core material of the present
invention is easy to manufacture, and has excellent properties of
less leaching of core material, generating almost no odor from the
wall material, having good storage stability since aggregation or
precipitation when blended in cosmetics is suppressed. Moreover,
since the capsule wall has high membrane strength, it is possible
to reduce the thickness of the capsule wall and the effect of the
core material can be exhibited sufficiently.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] FIG. 1 The electron micrograph of the microcapsule
containing core material prepared in Example 1.
[0045] FIG. 2 The particle size distribution of the micro capsules
containing core material prepared in Example 1.
[0046] FIG. 3 The particle size distribution of the microcapsules
containing core material prepared in Reference Example 1.
MODES FOR CARRYING OUT THE INVENTION
[0047] First, the silylated amino acid and the silane compound will
be described which are materials used in the manufacture of the
microcapsules containing core material of the first embodiment or
the second embodiment.
[Silylated Amino Acid]
[0048] Alfa amino acids used in the preparation of the silylated
amino acids are not particularly limited if they have been used in
cosmetics. For example, any of acidic amino acids such as aspartic
acid, glutamic acid or the like, neutral amino acids such as
glycine, alanine, serine, threonine, methionine, cysteine, valine,
leucine, isoleucine, phenylalanine, tyrosine, proline,
hydroxyproline, tryptophan, asparagine, glutamine or the like and
basic amino acids such as arginine, lysine, histidine, ornithine or
the like can be used.
[0049] As the .alpha. amino acid constituting the silylated amino
acid, as described above, hydrophilic amino acids are preferred.
Therefore, silylated amino acids having both a hydrophobic portion
and a hydrophilic portion are preferred. Here, hydrophilic amino
acids mean amino acids having the solubility in water at 25.degree.
C. of 10% or more. Examples of the hydrophilic amino acids include
aspartic acid, glutamic acid, glycine, alanine, serine, proline and
the like. Among the hydrophilic amino acids, use of neutral amino
acid having no charge is preferred, since efficient encapsulation
of the dispersed phase can be achieved and stronger capsules with
superior stability can be obtained. That is, neutral amino acids
such as serine, glycine, alanine, proline and the like are more
preferred.
[0050] The silylated amino acid in which a silyl group represented
by the above described general formula (III) is bonded to an amino
group of an amino acid can be obtained by reacting a silane
coupling agent which will generate two or more hydroxyl groups
bonded to silicon atom with an amino group of an amino acid. As the
silane coupling agent which will generate two or more hydroxyl
groups bonded to silicon atom, for example,
3-glycidoxypropyltrimethoxysilane,
3-glycidoxypropyltriethoxysilane,
3-glycidoxypropylmethyldimethoxysilane,
3-glycidoxypropylmethyldiethoxysilane,
3-methacryloxypropyltrimethoxysilane,
3-methacryloxypropylmethyldimethoxysilane,
3-methacryloxypropyltriethoxysilane,
3-methacryloxypropylmethyldiethoxysilane,
N-(2'-aminoethyl)-3-aminopropyltriethoxysilane,
N-(2'-aminoethyl)-3-aminopropylmethyldiethoxysilane and the like
can be mentioned. In any of the above-mentioned agents,
commercially available one can be used. For example, KBM-403,
KBM-402, KBE-403, KBE-402, KBM-502, KBM-503, KBE-502, KBE-503,
KBM-602, KBM-603, KBE-603 (all trade names) manufactured by
Shin-Etsu Chemical Co., SH6020, SZ6023, SZ6030, SH6040 (all trade
names) manufactured by Toray Dow Corning Co., Ltd. and the like
correspond to those commercially available.
[0051] The silylated amino acid can be produced by a production
method described in JP-A-8-59424 and JP-A-8-67608. Specifically,
first, a silane coupling agent having two or more hydroxyl groups
bonded to silicon atom is produced. The silane coupling agent
having two or more hydroxyl groups bonded to silicon atom, thus
produced, is added dropwise to an .alpha. amino acid solution with
sirring and warming, under a basic condition of pH9-11, to make
them to contact each other. Thereby the silane coupling agent is
bonded to the amino group of the .alpha. amino acid, and the amino
acid is obtained which has a silyl functional group having two or
more hydroxyl groups bonded to silicon atom as shown in the general
formula (III).
[0052] A silane coupling agent having two or more of hydroxyl
groups bonded to silicon atom can be prepared, for example, by
stirring an acidic or basic aqueous solution of a silane coupling
agent having alkoxy groups bonded to silicon atom at 30-50.degree.
C. for 5-20 min to convert the alkoxy groups bonded to the silicon
atom to hydroxyl groups. When a silane coupling agent having alkoxy
groups bonded to silicon atom is added dropwise into solution in a
range of pH 9-11 to react with an amino acid, the alkoxy groups are
hydrolyzed and converted to hydroxyl groups. That is, it is not
necessary to hydrolyze the silane coupling agent having alkoxy
groups in advance, and the reaction can be carried out directly by
adding the silane coupling agent having alkoxy groups to an aqueous
amino acid solution in which the pH is adjusted to 9-11.
[0053] The amino acid used in the reaction may be one kind of amino
acid or a mixture of two or more amino acids. However, reactivities
with the silane coupling agent are different depending on the amino
acids, and when using a mixture of amino acids, the extents of the
coupling reaction producing silylated amino acids which will be
used for the construction of capsule wall, will decrease.
Therefore, for producing the mixture of two or more kinds of
silylated amino acid, it is desirable to prepare each silylated
amino acid independently and mix them when the preparation of
microcapsules is conducted.
[0054] Progress and end of the reaction can be confirmed by
measuring the amino nitrogen content in the reaction solution by
Van Slyke method. After completion of the reaction, the
concentration is adjusted and then, the reaction product is
subjected to the following capsule wall formation reaction of
microcapsules with a silane compound. Alternatively, the reaction
mixture obtained as described above can be neutralized, suitably
concentrated, treated with ion-exchange resin, subjected to
dialysis, electrodialysis and/or ultrafiltration, and the like to
remove unreacted substances and impurities, then used for the
starting material of the co-polycondensation with silane
compound.
[Silane Compound Used for Forming the Capsule Wall of the
Microcapsule]
[0055] Next, the silylated amino acid obtained as described above
is reacted with one or more silane compounds represented by the
general formula (IV) to prepare a prepolymer for the capsule and
form the capsule wall of the microcapsule. Silane compound
represented by the general formula (IV) can be produced by
hydrolysis of a silane compound represented by the following
general formula (V):
R.sup.21.sub.psiX.sub.(4-p) (V) [0056] wherein, p is an integer
from 0 to 2, R.sup.21 is an alkyl group having 1 to 20 carbon atoms
or a phenyl group, p of R.sub.21 may be the same or different,
(4-p) of X are selected from the group consisting of a hydrogen
atom, hydroxyl group, alkoxy groups having 1 to 6 carbon atoms,
halogen groups, carboxy groups and amino groups.
[0057] Examples of the silane compounds represented by formula (V)
include; tetramethoxysilane, methyltrimethoxysilane,
ethyltrimethoxysilane, dimethyldimethoxysilane,
phenyltrimethoxysilane, diphenyldimethoxysilane,
n-propyltrimethoxysilane, diisopropyldimethoxysilane,
isobutyltrimethoxysilane, diisobutyldimethoxysilane,
hexyltrimethoxysilane, decyltrimethoxysilane,
octadecyltrimethoxysilane, phenyltrimethoxysilane,
tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane,
octyltriethoxysilane, phenyl triethoxysilane,
diphenyldiethoxysilane, hexyltriethoxysilane,
methyltrichlorosilane, dimethyldichlorosilane,
phenyltrichlorosilane, diphenyldichlorosilane, and the like.
[0058] The silane compound represented by the general formula (V)
may be a commercially available product. Examples of the
commercially available product include; KBM-22, KBM-103, KBE-13,
KBE-22, KBE-103, KA-12, KA-13, KA-103, KA-202 (all trade names)
manufactured by Shin-Etsu Chemical Co., Ltd., Z-6366, Z-6329,
Z-6124, Z-6265, Z-6258, Z-2306, Z-6275, Z-6403, Z-6124, Z-6586,
Z-6341, Z-6586, ACS-8 (all trade names) manufactured by Toray Dow
Corning Co., Ltd. and the like.
[0059] Next, the continuous phase and the dispersed phase where
co-polycondensation of the silylated amino acid and the silane
compound is performed, and the production method of microcapsules
containing core material will be described.
[Continuous Phase and Dispersed Phase]
[0060] In the manufacture of microcapsules containing core
material, the dispersion, where co-polycondensation of the
silylated amino acid and the silane compound represented by the
general formula (V) is performed, is prepared by dispersing a
dispersed phase in a continuous phase.
[0061] An aqueous solvent may be used as the continuous phase and
an oily substance may be used as the dispersed phase, as well as an
oily substance may be used as the continuous phase and an aqueous
material may be used as the dispersed phase. In either case, the
manufacture of the capsule is possible, and micro capsules
containing the dispersed phase as core material can be obtained.
However, microcapsules containing an oily substance which is
produced by using an aqueous solvent as the continuous phase and an
oily substance as the dispersed phase can be microcapsules having
stronger capsule wall and causing almost no leaching of core
material, therefore, are more preferred.
[0062] Examples of material which can be used as the core material
of microcapsule and used in the dispersion phase include;
water, aqueous solutions of water-soluble substance, higher fatty
acids, hydrocarbons, organic solvents, esters, phenols, silicones,
silanes, metal alkoxides, higher alcohols, animal and vegetable
oils, animal and plant extracts, electron-donating coloring organic
compounds, dyes, ultraviolet absorbers, vitamins, medicinal
ingredients, flavor components, salts, amino acids, proteins,
sugars, enzymes, fluorocarbonmaterials, and the like. The core
material can be one of above substances or mixture of two or more
of them.
[Production of the Microcapsule Containing Core Material]
[0063] Co-polycondensation of a silylated amino acid and a silane
compound represented by the general formula (V) can be carried out
according to the production method of the microcapsules having
capsule wall made of a copolymer of silylated peptide and silane
compound described in Patent Document 3 and Patent Document 4. That
is, when the core material (the contained material) is an oily
substance, firstly, a prepolymer is prepared by reacting a silane
compound represented by the general formula (IV), which is a
hydrolyzate of a silane compound represented by the general formula
(V), with a silylated amino acid in an aqueous solution. In the
reaction, the silane compound represented by the general formula
(V) is hydrolyzed in advance in an acidic or a basic solution to
form the silane compound represented by the general formula (IV),
followed by a reaction with the silylated amino acid. However, the
reaction of the silane compound represented by the general formula
(IV) with the silylated amino acid is usually carried out under
acidic conditions of pH4 or lower pH or basic conditions of pH9 or
higher pH, and, under the pH conditions, the silane compound
represented by the general formula (V) is hydrolyzed to the silane
compound represented by the general formula (IV). Therefore,
hydrolyzation of the silane compound represented by general formula
(V) in advance to obtain the silane compound represented by the
general formula (IV) is not necessary.
[0064] Specifically, although, when the core material is an oily
substance, the conditions are not particularly limited, the
prepolymer can be obtained by the reaction described next.
[0065] The aqueous solution of silylated amino acid is adjusted to
pH1-5, preferably pH2-4, [0066] the silane compound represented by
the general formula (V) is added dropwise to the solution at a
temperature of -5-90.degree. C., preferably 5-75.degree. C., more
preferably 40-60.degree. C., with stirring at 100-400 rpm,
preferably 200-300 rpm, [0067] after completion of the addition,
the reaction is continued with stirring at 40-60.degree. C., and
then pH of the solution is adjusted to about 5-7. As the acidic
agent for pH adjustment in the manufacture, for example, inorganic
acids such as hydrochloric acid, sulfuric acid, phosphoric acid or
the like; organic acids such as acetic acid or the like can be
used. As the alkali agent, for example, sodium hydroxide, potassium
hydroxide or the like can be used.
[0068] Next, with stirring the dispersion containing prepolymer
prepared as described above at 500-700 rpm, preferably at about
550-650 rpm, a phase to become the core material is added over 30
minutes to 3 hours at 30-70.degree. C., preferably at 45-55.degree.
C. After completion of the addition, the dispersion is stirred more
for 2-5 hours by a homomixer at 5,000-15,000 rpm, preferably
8,000-12,000 rpm to fully perform emulsification thereby a capsule
wall is formed.
[0069] When the core material is an aqueous substance, after
preparation of the prepolymer, a large amount of oily substance is
added, with stirring at 500-700 rpm, preferably at about 600 rpm,
to reverse the phase and microcapsules containing an aqueous
substance as the core material can be obtained.
[0070] Thereafter, distillation operation of generated alcohol and
pH adjustment are carried out and microcapsules containing core
material can be obtained. After the microcapsules containing core
material are obtained, they may be treated further with the silane
compound represented by the above described general formula (V),
for strengthening the capsule wall (capsule wall strengthening
treatment). However, when the core material is a light sensitive
agent, such as ultraviolet absorber, there is a possibility that
activity of ultraviolet absorption is reduced if the capsule wall
is too thick. In addition, there is a possibility to feel the
foreign body sensation when applied on skin if the capsule wall
becomes too thick and the capsules become hard. Therefore, the
extent of the capsule wall strengthening treatment must be
determined properly based on the usage of the microcapsule
containing core material.
[0071] Although it is possible to obtain microcapsules containing
material as described above, unreacted hydroxyl groups may remain
in the co-polycondensate constituting the capsule wall. If hydroxyl
groups remain, the hydroxy groups on the capsule surface may bond
to each other which may cause aggregation and precipitation of the
capsules. Therefore, it is preferable to carry out surface
treatment of capsules to prevent aggregation of the microcapsules
containing core material obtained as described above.
[0072] The surface treatment of capsules is carried out by using a
silane compound having one hydroxyl group bonded to silicon atom
represented by the following general formula (VI):
R.sup.4.sub.3SiOH (VI) [0073] wherein R.sup.4 is an alkyl group
having 1 to 4 carbon atoms or a phenyl group, the three alkyl
groups may be the same or different each other, to block the
hydroxyl groups in the co-polycondensate constituting the capsule
wall.
[0074] The silane compound having one hydroxyl group represented by
the general formula (VI) can be obtained by hydrolysis of a silane
compound represented by the general formula (VII):
R.sup.4.sub.3Si--R.sup.5 (VII) [0075] wherein, R.sup.4 is an alkyl
group having 1 to 4 carbon atoms or a phenyl group, the three alkyl
groups may be the same or different each other, R.sup.5 is an
alkoxy group having 1 to 6 carbon atoms or a halogen atom.
[0076] Examples of the silane compound represented by the general
formula (VII) include;
trimethylsilylchloride(trimethylchlorosilane),
triethylsilylchloride(triethylchlorosilane),
t-butyldimethylsilylchloride(t-butyldimethylchloro silane),
triisopropylsilylchloride (triisopropyl chlorosilane),
trimethylethoxysilane, triphenylethoxysilane and the like.
Commercially available products can be used as the above compound.
As commercially available products, for example, LS-260, LS-1210,
LS-1190, TIPSC (all trade names) manufactured by Shin-Etsu Chemical
Co., Ltd., Z-6013 (trade name) manufactured by Toray Dow Corning
Co., Ltd. and the like can be mentioned.
[0077] The surface treatment such as capsule wall strengthening
treatment and treatment for preventing aggregation of the capsules
can be carried out either by adding the silane compound, in which a
hydroxyl group was generated by hydrolysis in advance, to the
solution containing the capsules, or by adjusting pH of the
solution to a pH where the silane compound to be used for the
treatment hydrolyzes, followed by adding the silane compound to the
solution. That is, the treatment can be carried out by adjusting pH
of the solution containing the capsules to pH 2-4, followed by
adding a silane compound represented by the general formula (VII)
to the solution with stirring the solution preferably in the range
of 40-75.degree. C. at 300-800 rpm. After completion of the
addition, the reaction is continued for an additional 2-5 hours
with stirring for sufficient progress of the reaction.
[0078] Next, cosmetics containing the above described microcapsules
containing core material of the present invention (the first
embodiment, the second embodiment) will be described.
[Cosmetics Comprising Microcapsules Containing Core Material]
[0079] A cosmetic of the present invention is prepared by
compounding microcapsules containing core material having capsule
wall made of a silylated amino acid/silane compound copolymer
manufactured as mentioned above. As examples of the cosmetic, skin
cosmetics such as skin creams, milky lotions, cleansing liquids,
cleansing creams, skin care gels, essences, sunscreen creams, and
the like, and hair cosmetics such as hair rinses, hair treatments,
hair conditioners, hair creams, split hair coating agents,
shampoos, hair setting agents, hair dyes, agents for a permanent
wave, and the like can be mentioned.
[0080] Content of the microcapsule containing core material of the
present invention (the first embodiment, the second embodiment) in
the cosmetic of the present invention (amount in the cosmetic)
varies depending on the type of the cosmetic, but, in many cases,
the content is preferably 0.01% by mass-35% by mass, and more
preferably 1% by mass-20% by mass. When content of the microcapsule
containing core material is less than the above range, it may not
be possible to exhibit the effect of the core material. When
content of the microcapsule containing core material in the
cosmetic is more than the above range, stickiness, roughness or
foreign body sensation occurs sometimes.
[0081] The cosmetic of the present invention contains microcapsules
containing core material of the present invention as an essential
component, and may contain anionic surfactants, nonionic
surfactants, cationic surfactants, amphoteric surfactants, cationic
polymers, amphoteric polymers, anionic polymers, thickeners, animal
and plant extracts, polysaccharides or derivatives thereof,
hydrolysates of the proteins from animals, plants or microorganisms
and derivatives thereof, a neutral or acidic amino acids, wetting
agents, lower alcohols, higher alcohols, fats and oils, silicones,
various dyes and pigments, preservatives, perfumes, and the like,
as long as the gist of the present invention is not impaired.
EXAMPLES
[0082] Then, the present invention will be illustrated with
reference to examples, but the scope of the present invention is
not limited to these examples. Prior to the examples, production
examples of silylated amino acids used in Examples are described.
Any "%" described in the following examples and production examples
are "mass %".
Production Example 1: Production of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]serine
(Silylated Serine)
[0083] Into a 1 liter beaker, 30 g (0.285 mol) of serine and, then,
270 g of water were added. The resulting mixture was stirred and
adjusted to pH9.2 by addition of 25% aqueous sodium hydroxide.
[0084] The resulting solution was warmed to 50.degree. C. To the
warmed solution, 3-glycidoxypropyltriethoxysilane [KBE-403 (trade
name); manufactured by Shin-Etsu Chemical Co., Ltd.] 79.5 g (0.286
mol; equimolar amounts of serine) was added dropwise over about 2
hours with stirring and stirring was continued for 16 hours at
50.degree. C. after completion of the addition. Thereafter, 17%
aqueous hydrochloric acid was added to adjust to pH6.0 and the
solution was stirred for 1 hour at 80.degree. C. and then cooled to
obtain 403.9 g of an aqueous solution of
N-[2-hydroxy-3-(3'-trihydroxysilyl)propoxy]propyl]serine (silylated
serine) having the solid concentration of 18.2%. The extent of the
reaction calculated based on the amino nitrogen contents before and
after the reaction was 75.6%. As the result, moles of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]serine was
calculated and determined to be 0.186.
[0085] The reaction solutions before and after the reaction were
analyzed by liquid chromatography under the following conditions
(HPLC, hereinafter referred to as HPLC). After the reaction, the
peak in the vicinity of molecular weight 105 of the raw material of
serine almost disappeared, and a new peak near 298, the molecular
weight of N-[2-hydroxy-3-[3'-(trihydroxysilyl)
propoxy]propyl]serine, was detected. Thus, it was confirmed that
N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]serine was
produced.
[0086] [Analysis conditions of liquid chromatography (HPLC)]
Separation column: TSKgel G3000PW.times.L (diameter 7.8
mm.times.length 300 mm)
[0087] Eluent: 0.1% aqueous trifluoroacetic
acid/acetonitrile=55/45
[0088] Flow rate: 0.3 mL/min
[0089] Detector: RI (differential refractive index) detector and UV
(ultraviolet) detector (210 nm)
[0090] Standard samples: glutathione (Mw307), bradykinin (Mw1,060),
insulin B chain (Mw3,496), aprotinin (Mw6,500)
Production Example 2: Production of
N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]glycine
[0091] In the same manner as in production example 1 except for
using glycine 30 g (0.4 mol) instead of serine and using
3-glycidoxypropyl triethoxysilane 111.2 g (0.4 mol, equimolar
amounts of glycine), 432.7 g of an aqueous solution of
N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]glycine
(silylated glycine) having the solid concentration of 22.9% was
obtained. The extent of the reaction calculated based on the amino
nitrogen contents before and after the reaction was 62.2%. As the
result, moles of N-[2-hydroxy-3-[3'-(trihydroxysilyl)
propoxy]propyl]glycine was calculated and determined to be
0.23.
[0092] As a result of HPLC analysis under the same conditions as in
production example 1, the peak of molecular weight of about 75 of
glycine prior to reaction disappeared after the reaction, a peak
was detected around 268 and it was confirmed that
N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]glycine was
produced.
Production Example 3: Production of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]aspartic Acid
(Silylated Aspartic Acid)
[0093] In the same manner as in production example 1 except for
using aspartic acid 30 g (0.225 mol) instead of serine and using
3-glycidoxypropyl triethoxysilane 55.8 g (0.225 mol, equimolar
amounts of aspartic acid), 365.8 g of solution of
N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]aspartic acid
(silylated aspartic acid) having the solid concentration of 17.4%
was obtained. The extent of the reaction calculated based on the
amino nitrogen contents before and after the reaction was 78%. As
the result, moles of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]aspartic acid
was calculated and determined to be 0.15.
[0094] As a result of HPLC analysis under the same conditions as in
production example 1, the peak of molecular weight of about 133 of
aspartic acid prior to reaction disappeared after the reaction, a
new peak was detected around 330 and it was confirmed that
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]aspartic acid
was produced.
Production Example 4: Production of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]glutamic Acid
(Silylated Glutamic Acid)
[0095] In the same manner as in production example 1 except for
using glutamic acid 50 g (0.340 mol) instead of serine and using
3-glycidoxypropyl triethoxysilane 94.6 g (0.340 mol, equimolar
amounts of glutamic acid), 1070.9 g of a solution of
N-[2-hydroxy-3-[3'-(trihydroxy silyl)propoxy]propyl]glutamic acid
(silylated glutamic acid) having the solid concentration of 11.4%
was obtained. The extent of the reaction calculated based on the
amino nitrogen contents before and after the reaction was 63.3%. As
the result, moles of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]glutamic acid
was calculated and determined to be 0.28.
[0096] As a result of HPLC analysis under the same conditions as in
production example 1, the peak of molecular weight of about 147 of
glutamic acid prior to reaction disappeared after the reaction, a
new peak was detected around 340 and it was confirmed that
N-[2-hydroxy3-[3'-(trihydroxysilyl)propoxy]propyl]glutamic acid was
produced.
Production Example 5: Production of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]lysine
(Silylated Lysine)
[0097] In the same manner as in production example 1 except for
using lysine hydrochloride 30 g (0.164 mol) instead of serine in
production example 1 and using 3-glycidoxypropyl triethoxysilane
45.7 g (0.164 mol, equimolar amounts of lysine), 378.0 g of
solution of
N-[2-hydroxy-3-(3'-trihydroxysilyl)propoxy]propyl]lysine (silylated
lysine) having the solid concentration of 13.5% was obtained. The
extent of the reaction calculated based on the amino nitrogen
contents before and after the reaction was 42.0%. Lysine has two
amino groups, and it seemed that 80% or more of silyl groups was
introduced to the amino group at .alpha.-position. As the result,
moles of N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]lysine
was calculated and determined to be 0.13.
[0098] As a result of HPLC analysis under the same conditions as in
production example 1, the peak of molecular weight of about 146 of
lysine prior to reaction disappeared after the reaction, peaks were
detected near the vicinity of 340 and 530, and it was confirmed
that N-[2-hydroxy-3-(3'-trihydroxysilyl)propoxy]propyl]lysine or
N,N'-di-[2-hydroxy-3-(3'-trihydroxysilyl)propoxy]propyl]lysine was
produced.
Production Example 6: Production of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]arginine
(Silylated Arginine)
[0099] In the same manner as in production example 1 except for
using arginine 40 g (0.23 mol) instead of serine in production
example 1 and using 3-glycidoxypropyl triethoxysilane 76.7 g (0.275
mol, 1.2 molar equivalent of arginine), 274.9 g of an aqueous
solution of
N-[2-hydroxy-3-(3'-trihydroxysilyl)propoxy]propyl]arginine(silylated
arginine) having the solid concentration 25.8% was obtained. The
extent of the reaction calculated based on the amino nitrogen
contents before and after the reaction was 85.9%. As the result,
moles of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]arginine was
calculated and determined to be 0.16.
[0100] As a result of HPLC analysis under the same conditions as in
production example 1, the peak of molecular weight of about 174 of
arginine prior to reaction disappeared after the reaction, a peak
was detected near the vicinity of 370, and it was confirmed that
N-[2-hydroxy-3-(3'-trihydroxysilyl) propoxy]propyl]arginine was
produced.
Production Example 7: Production of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]alanine
(Silylated Alanine)
[0101] In the same manner as in production example 1 except for
using alanine 30 g (0.337 mol) instead of serine in production
example 1 and using 3-glycidoxypropyl triethoxysilane 93.8 g (0.337
mol, equimolar amounts of alanine), 317.7 g of a solution of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]alanine
(silylated alanine) having the solid concentration of 25.3% was
obtained. The extent of the reaction calculated based on the amino
nitrogen contents before and after the reaction was 70.3%. As the
result, moles of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]alanine was
calculated and determined to be 0.2.
[0102] As a result of HPLC analysis under the same conditions as in
production example 1, the peak of molecular weight of about 89 of
alanine prior to reaction disappeared after the reaction, a new
peak was detected near the vicinity of 280, and it was confirmed
that N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]alanine was
produced.
Production Example 8: Production of
N-[2-hydroxy-3-[3'-(dihydroxymethylsilyl)propoxy]propyl]serine
(Silylated Serine)
[0103] Into a 1 liter beaker, 30 g (0.285 mol) of serine and, then,
270 g of water were added. The resulting mixture was stirred and
adjusted to pH9.2 by addition of 25% aqueous sodium hydroxide. The
resulting solution was warmed to 60.degree. C. To the warmed
solution, 3-glycidoxypropylmethyldiethoxysilane [KBE-402 (trade
name); manufactured by Shin-Etsu Chemical Co., Ltd.] 70.7 g (0.285
mol, equimolar amounts of serine) was added dropwise over about 2
hours with stirring and stirring was continued for 16 hours at
60.degree. C. after the dropwise addition. Thereafter, 17% aqueous
hydrochloric acid was added to adjust to pH6.0 and the solution was
stirred for 1 hour at 80.degree. C. and then cooled to obtain 458.9
g of an aqueous solution of
N-[2-hydroxy-3-(3'-dihydroxymethylsilyl) propoxy]propyl]serine
(silylated serine) having the solid concentration of 18.4%. The
extent of the reaction calculated based on the amino nitrogen
contents before and after the reaction was 77%. As the result,
moles of
N-[2-hydroxy-3-[3'-(dihydroxymethylsilyl)propoxy]propyl]serine was
calculated and determined to be 0.22.
Example 1: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Serine and Methyltriethoxysilane
and Containing an Ultraviolet Absorber
[0104] Into a 2 liter glass lid circular reactor, 131.9 g of 18.2%
aqueous solution of silylated serine
(N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]serine) (about
0.061 mole of silylated serine) prepared in production example 1
was charged. Then, 68.1 g of water was added to adjust the solid
concentration to 12%, and 17% aqueous hydrochloric acid was added
to adjust to pH2.2.
[0105] The resulting solution was warmed to 50.degree. C. and to
the solution, methyltriethoxysilane [KBE-13 (trade name);
manufactured by Shin-Etsu Chemical Co., Ltd.] 33.5 g (0.188 mol)
was added dropwise with stirring over about 30 minutes. After the
completion of the addition, stirring was continued for 4 hours at
50.degree. C. Then, aqueous sodium hydroxide was added dropwise to
adjust pH of the solution to 6.0, and thereto, 2-ethylhexyl
p-methoxycinnamate 345.1 g was added dropwise over 2.5 hours with
stirring at 600 rpm. Thereafter, the solution was stirred at 10,000
rpm using a homomixer at 50.degree. C., and finely emulsified.
[0106] Next, for the surface treatment of capsule wall for
preventing aggregation, trimethylchlorosilane [LS-260 (trade name)
manufactured by Shin-Etsu Chemical Co., Ltd.] 5.1 g was added to
the resulting emulsion with stirring at 400 rpm at 50.degree. C.,
the pH was adjusted to 6.0 with 5% aqueous sodium hydroxide, and
the resulting reaction solution was heated to reflux. After
distilling off the vapor containing alcohol, the reflux was further
continued for 2 hours with stirring at 400 rpm.
[0107] The resulting reaction solution was slowly cooled to room
temperature with stirring at 100 rpm and 645.7 g of dispersion of
microcapsule (solid concentration 60.6%) containing 2-ethylhexyl
p-methoxycinnamate (ultraviolet absorber) and having capsule wall
made of a co-polycondensate of silylated serine and
methyltriethoxysilane was obtained.
[0108] The resulting capsule dispersion was observed with electron
microscope, and it was confirmed that microcapsules having the
particle size of about 2 .mu.m were generated, as shown in FIG. 1.
Further, the resulting microcapsule dispersion was measured by
particle size distribution analyzer described below, and it was
confirmed that the capsules have an average particle diameter of
1.553 .mu.m with a narrow distribution range of standard deviation
of 0.229 as shown in FIG. 2.
Example 2: Production of Micro Capsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Glycine and Methyltriethoxysilane
and Containing an Ultraviolet Absorber
[0109] Into a 2 liter glass lid circular reactor, 78.6 g of 22.9%
aqueous solution of silylated glycine
(N-[2-hydroxy-3-[3'-trihydroxysilyl)propoxy]propyl]glycine) (about
0.042 mole of silylated glycine) prepared in production example 2
was charged. Then, 221.4 g of water was added to adjust the solid
concentration to 6%, and 17% aqueous hydrochloric acid was added to
adjust to pH2.2.
[0110] The resulting solution was warmed to 50.degree. C. and to
the solution, methyltriethoxysilane 36.3 g (0.202 mol) was added
dropwise with stirring over about 30 minutes. After the completion
of the dropwise addition, stirring was continued for 4 hours at
50.degree. C.
[0111] Then, an aqueous sodium hydroxide was added dropwise to
adjust the pH of the solution to 6.0, and thereto, 2-ethylhexyl
p-methoxycinnamate 362.7 g was added dropwise over 2.5 hours with
stirring at 600 rpm. Thereafter, the solution was stirred at 10,000
rpm using a homomixer at 50.degree. C., and finely emulsified.
[0112] With stirring the resulting emulsion at 400 rpm at
50.degree. C., trimethylchlorosilane 5.5 g was added for the
surface treatment of capsule wall for preventing aggregation, pH
was adjusted to 6.0 with 5% aqueous sodium hydroxide, and the
resulting reaction solution was heated to reflux. After distilling
off the vapor containing alcohol, the reflux was further continued
for 2 hours with stirring at 400 rpm.
[0113] The resulting reaction solution was slowly cooled to room
temperature with stirring at 100 rpm and 683 g of dispersion of
microcapsules (solid concentration 58.3%) containing 2-ethylhexyl
p-methoxycinnamate and having capsule wall made of a
co-polycondensate of silylated glycine and methyltriethoxysilane
was obtained.
Example 3: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Aspartic Acid and
Methyltriethoxysilane and Containing an Ultraviolet Absorber
[0114] In the same manner as in example 1 except for using 138 g of
17.4% aqueous solution of silylated aspartic acid
(N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]aspartic acid)
produced in production example 3 as the raw material silylated
amino acid, changing the amounts of water for adjusting the
concentration to 62.0 g, of methyltriethoxysilane to 41.6 g, and of
2-ethylhexyl p-methoxycinnamate to be contained to 270.2 g, and
using 3.3 g of trimethylchloro silane as the silane compound for
the surface treatment of capsule wall, 570.7 g of dispersion of
microcapsules (solid concentration 58.2%) having capsule wall made
of a co-polycondensate of silylated aspartic acid and
methyltriethoxysilane and containing 2-ethylhexyl
p-methoxycinnamate was obtained.
Example 4: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Glutamic Acid and
Methyltriethoxysilane and Containing an Ultraviolet Absorber
[0115] In the same manner as in example 2 except for using 92.2 g
of 11.4% aqueous solution of silylated glutamic acid
(N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]glutamic acid)
produced in production example 4 as the raw material silylated
amino acid, changing the amounts of water for adjusting the
concentration to 82.8 g, of methyltriethoxysilane to 44.0 g and of
2-ethylhexyl p-methoxycinnamate to be contained to 324.5 g, and
using 2.7 g of trimethylchloro silane as the silane compound for
the surface treatment of capsule wall, 590 g of dispersion of
microcapsules (solid concentration 60.9%) having capsule wall made
of a co-polycondensate of silylated glutamic acid and
methyltriethoxysilane and containing 2-ethylhexyl
p-methoxycinnamate was obtained.
Example 5: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Lysine and Methyltriethoxysilane
and Containing an Ultraviolet Absorber
[0116] In the same manner as in example 2 except for using 88.8 g
of 13.5% aqueous solution of silylated lysine
(N-[2-hydroxy-3-[3'-(trihydroxysilyl) propoxy]propyl]lysine)
produced in production example 5 as the raw material silylated
amino acid, changing the amounts of water for adjusting the
concentration to 111.2 g, of methyltriethoxysilane to 44.0 g and of
2-ethylhexyl p-methoxycinnamate to be contained to 305.7 g, and
using 3.1 g of trimethylchlorosilane as the silane compound for the
surface treatment of capsule wall, 570.7 g of dispersion of
microcapsules (solid concentration 58.2%) having capsule wall made
of a co-polycondensate of silylated lysine and
methyltriethoxysilane and containing 2-ethylhexyl
p-methoxycinnamate was obtained.
Example 6: Production of Micro Capsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Arginine and Methyltriethoxysilane
and Containing an Ultraviolet Absorber
[0117] In the same manner as in example 2 except for using 46.4 g
of 25.8% aqueous solution of silylated arginine
(N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]arginine)
produced in production example 6 as the raw material silylated
amino acid, changing the amounts of water for adjusting the
concentration to 153.6 g, of methyltriethoxysilane to 47.3 g and of
2-ethylhexyl p-methoxycinnamate to be contained to 153.6 g, and
using trimethylchlorosilane 2.9 g and trimethylethoxysilane 9.4 g
as the silane compound for the surface treatment of capsule wall,
306.2 g of dispersion of microcapsules (solid concentration 60.7%)
having capsule wall made of a co-polycondensate of silylated
arginine and methyltriethoxysilane and containing 2-ethylhexyl
p-methoxycinnamate was obtained.
Example 7: Production of Micro Capsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Alanine and Methyltriethoxysilane
and Containing an Ultraviolet Absorber
[0118] In the same manner as in example 2 except for using 47.3 g
of 25.3% aqueous solution of silylated alanine
(N-[2-hydroxy-3-[3'-(trihydroxy silyl)propoxy]propyl]alanine)
produced in production example 7 as the raw material silylated
amino acid, changing the amounts of water for adjusting the
concentration to 152.7 g, of methyltriethoxysilane to 34.9 g and of
2-ethylhexyl p-methoxycinnamate to be contained to 250.1 g, and
using 3.5 g of trimethylchlorosilane as the silane compound for the
surface treatment of capsule wall, 451.9 g of dispersion of
microcapsules (solid concentration 60.2%) having capsule wall made
of a co-polycondensate of silylated alanine and
methyltriethoxysilane and containing 2-ethylhexyl
p-methoxycinnamate was obtained.
Example 8: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Serine, Silylated a Spartic Acid
and Methyltriethoxysilane and Containing an Ultraviolet
Absorber
[0119] In the same manner as in example 1 except for using a
mixture of 63.8 g of 18.2% aqueous solution of silylated serine
produced in production example 1 and 69 g of 17.4% aqueous solution
of silylated aspartic acid produced in production example 3 as the
raw material silylated amino acid, changing the amounts of water
for adjusting the concentration to 67.2 g, of methyltriethoxy
silane to 40 g and of 2-ethylhexyl p-methoxycinnamate to be
contained to 306.2 g, and using 5.1 g of trimethylchlorosilane as
the silane compound for the surface treatment of capsule wall,
543.6 g of dispersion of microcapsules (solid concentration 60.5%)
having capsule wall made of a co-polycondensate of silylated
serine, silylated aspartic acid and methyltriethoxysilane and
containing 2-ethylhexyl p-methoxycinnamate was obtained.
Example 9: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Glycine, Methyltriethoxysilane and
Phenyltriethoxysilane Containing Dimethylpolysiloxane
[0120] In the same manner as in example 2 except for using 78.6 g
of 22.9% aqueous solution of silylated glycine
(N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]glycine)
produced in production example 2 as the raw material silylated
amino acid, changing the amount of water for adjusting the
concentration to 223.4 g, using a mixture of 37.4 g (0.21 mol) of
methyltriethoxysilane and 10 g (0.04 mol) of phenyltriethoxysilane
as the silane compound, using 448.2 g of dimethylpolysiloxane
[KF-96A-1000cs (trade name) manufactured by Shin-Etsu chemical Co.,
Ltd.] to be contained, and using 11.7 g of trimethylchlorosilane as
the silane compound for the surface treatment of capsule wall, 806
g of dispersion of microcapsules (solid concentration 61%) having
capsule wall made of a co-polycondensate of silylated glycine,
methyltriethoxysilane and phenyltriethoxysilane and containing
dimethylpolysiloxane was obtained.
Example 10: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Serine and Methyltriethoxysilane
Containing Ascorbyl Tetrahexyldecanoate
[0121] Into a 2 liter glass lid circular reactor, 131.9 g of 18.2%
aqueous solution of silylated serine prepared in production example
1 was charged. Then, 88.1 g of water was added to adjust the solid
concentration to 12%, and 17% aqueous hydrochloric acid was added
to adjust to pH2.2.
[0122] The resulting solution was warmed to 50.degree. C. and to
the solution, methyltriethoxysilane 33.5 g was added dropwise with
stirring over about 30 minutes. After the completion of the
dropwise addition, stirring was continued for 4 hours at 50.degree.
C.
[0123] Then, 25% aqueous sodium hydroxide was added dropwise to
adjust the pH of the solution to 6.0, and thereto, ascorbyl
tetrahexyldecanoate [Wako Pure Chemical Industries, Ltd.] 218.9 g
was added dropwise over 2.5 hours with stirring at 600 rpm.
[0124] Thereafter, trimethylchlorosilane 2.7 g was added thereto at
50.degree. C., with stirring at 400 rpm, and 5% aqueous sodium
hydroxide was added to adjust to pH6.0. Under reduced pressure at
40.degree. C., 104.5 g of the solvent of the reaction solution was
distilled off with a rotary evaporator, and 313.5 g of dispersion
of the microcapsules (solid concentration 87.9%) having capsule
wall made of a co-polycondensate of silylated serine and
methyltriethoxysilane and containing ascorbyl tetrahexyldecanoate
was obtained.
Example 11: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Aspartic Acid,
Methyltriethoxysilane and Phenyltriethoxysilane Containing
Squalane
[0125] Into a 2 liter glass lid circular reactor, 57.5 g of 17.4%
aqueous solution of silylated aspartic acid (about 0.02 mol of
silylated aspartic acid) prepared in production example 3 was
charged. Then, 42.5 g of water was added to adjust the solid
concentration to 12%, and 17% aqueous hydrochloric acid was added
to adjust to pH2.2.
[0126] The resulting solution was warmed to 50.degree. C., and to
the solution, a mixture of methyltriethoxysilane 23.1 g (0.133 mol)
and phenyltriethoxysilane 16 g (0.066 mol) was added dropwise with
stirring over about 30 minutes. After the completion of the
dropwise addition, stirring was continued for 4 hours at 50.degree.
C. Then, an aqueous sodium hydroxide was added dropwise to adjust
pH of the solution to 6.0, and thereto, squalane 240 g was added
dropwise over 1 hour with stirring at 600 rpm. Thereafter, the
solution was stirred at 10,000 rpm using a homomixer at 50.degree.
C., and finely emulsified.
[0127] Next, with stirring the resulting emulsion at 400 rpm at
50.degree. C., trimethylchlorosilane 5.1 g was added for the
surface treatment of capsule wall, pH was adjusted to 6.0 with 5%
aqueous sodium hydroxide, and the resulting reaction solution was
heated to reflux. After distilling off the vapor containing
alcohol, the reflux was further continued for 2 hours with stirring
at 400 rpm.
[0128] The resulting reaction solution was slowly cooled to room
temperature with stirring at 100 rpm and 430 g of dispersion of
microcapsules (solid concentration 88.1%) containing squalane with
solid concentration of 60% and having capsule wall made of a
co-polycondensate of silylatedaspartic acid, methyl triethoxysilane
and phenyl triethoxysilane was obtained.
Example 12: Production of Microcapsules Having Capsule Wall Made of
a Co-Polycondensate of Silylated Serine and Methyltriethoxysilane
and Octyltriethoxysilane Containing Water
[0129] Into a 2 liter glass lid circular reactor, 74.8 g of 24.5%
aqueous solution of
N-[2-hydroxy-3-[3'-(dihydroxymethylsilyl)propoxy]propyl]serine
(about 0.06 mol as silylated serine) prepared in production example
9 was charged. Then, 47.4 g of water was added to adjust the solid
concentration to 15%, and 17% aqueous hydrochloric acid was added
to adjust to pH2.0.
[0130] The resulting solution was warmed to 50.degree. C. and to
the solution, a mixture of methyltriethoxy silane 42.7 g (0.24 mol)
and octyltriethoxysilane 132.5 g (0.48 mol) was added dropwise with
stirring over about 30 minutes. After the completion of the
addition, stirring was continued for 16 hours at 50.degree. C.
[0131] Then, the stirring speed was increased to 600 rpm,
caprylic/capric Triglyceride 259 g to be the continuous phase was
added, stirring was continued until the phase inversion occurred,
then 20% aqueous sodium hydroxide was added to adjust to pH6, and
stirring was further continued at 50.degree. C. for 3 hours at 600
rpm.
[0132] Next, a mixture of trimethylchlorosilane 6.5 g (0.06 mol)
and trimethylethoxysilane 28.3 g (0.24 mol) was added with stirring
at 600 rpm, 50.degree. C., and then stirring was continued for 16
hours at 600 rpm, 50.degree. C. To the resulting reaction solution,
5% aqueous sodium hydroxide was added dropwise to adjust pH of the
solution to 6. The stirring speed was decreased to 400 rpm and the
reaction solution was gradually heated to 80.degree. C. and kept
under reflux for 2 hours to remove generated alcohol and water
present in the continuous phase. Then, with stirring at 400 rpm,
the temperature of the reaction solution was lowered to room
temperature, and 443 g of dispersion of microcapsules with about
40% water content in caprylic/capric Triglyceride was obtained
(calculated content of capsules was 50%).
[0133] Next, Reference examples are shown which are production
examples of microcapsules having capsule wall made by
co-polycondensation of a silylated peptide and a silane compound,
to be used as comparative products or comparative examples in the
performance evaluation tests and in examples.
[0134] Since protein hydrolyzate (hydrolysed peptide) constituting
the peptide portion of the silylated peptide is a mixture of
peptides of different molecular weights, measured value of the
amino acid polymerization degree is the average polymerization
degree of the peptide (average polymerization degree of amino
acid).
Reference Example 1: Production of Microcapsules Having Capsule
Wall Made of Co-Polycondensate of Silylated Hydrolyzed Casein and
Methyltriethoxysilane and Containing an Ultraviolet Absorber
[0135] Into a 1 liter beaker, 25% aqueous solution of casein
hydrolyzate (hydrolysed casein) 100 g (0.04 mol as moles calculated
from the amino nitrogen content) having average polymerization
degree of amino acid of 6 determined from the total nitrogen
content and the amino nitrogen content was charged and the pH was
adjusted to 9.5 by addition of 25% aqueous sodium hydroxide. The
resulting solution was warmed to 50.degree. C. To the warmed
solution, 3-glycidoxypropyltriethoxysilane 10 g (0.04 mol,
equimolar amounts of the amino nitrogen content of hydrolyzed
casein) was added dropwise over about 1 hour with stirring. After
completion of the dropwise addition, stirring was continued for 14
hours at 50.degree. C. Thereafter, 17% aqueous hydrochloric acid
was added to adjust the pH to 6.0 and 113 g of an aqueous solution
of N-[2-hydroxy-3-(3'-trihydroxysilyl)propoxy]propyl]hydrolyzed
casein (silylated hydrolyzed casein) having the solid concentration
of 28.8% was obtained.
[0136] The extent of the reaction calculated based on the amino
nitrogen contents before and after the reaction was 81%. As the
result, moles of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]hydrolyzed
casein was calculated and determined to be 0.03.
[0137] Next, the aqueous solution of silylated hydrolyzed casein,
thus prepared, was charged into a 2 liter glass lid circular
reactor. Then, 158 g of water was added to adjust the solid
concentration to 12%, and 17% aqueous hydrochloric acid was added
to adjust to pH2.2.
[0138] The resulting solution was warmed to 50.degree. C. and to
the solution, methyltriethoxysilane 21.3 g (0.12 mol) was added
dropwise with stirring over about 30 minutes. After the completion
of the dropwise addition, stirring was continued for 4 hours at
50.degree. C.
[0139] Then, aqueous sodium hydroxide was added dropwise to adjust
pH of the solution to 6.0, and thereto, 2-ethylhexyl
p-methoxycinnamate 394 g was added dropwise over 2.5 hours with
stirring at 600 rpm. Thereafter, the solution was stirred at 10,000
rpm using a homomixer at 50.degree. C., and finely emulsified.
[0140] Next, for the surface treatment of capsule wall,
trimethylchlorosilane 9.7 g was added to the resulting emulsion
with stirring at 400 rpm, 50.degree. C., pH was adjusted to 6.0
with 5% aqueous sodium hydroxide, and the resulting reaction
solution was heated to reflux. After distilling off the vapor
containing alcohol, the reflux was further continued for 2 hours
with stirring at 400 rpm.
[0141] The resulting reaction solution was slowly cooled to room
temperature with stirring at 100 rpm and solid concentration was
adjusted to 60% by adding water to obtain 617 g of aqueous
dispersion of microcapsules containing 2-ethylhexyl
p-methoxycinnamate and having capsule wall made of a
co-polycondensate of silylated hydrolyzed casein and
methyltriethoxysilane.
Reference Example 2: Production of Microcapsules Having Capsule
Wall Made of a Co-Polycondensate of Silylated Hydrolyzed Pea
Protein, Methyltriethoxysilane and Phenyltriethoxysilane and
Containing Dimethylpolysiloxane
[0142] Into a 1 liter beaker, 25% aqueous solution of pea protein
hydrolyzate (hydrolysed pea protein) 100 g (0.05 mol as moles
calculated from the amino nitrogen content) having average
polymerization degree of amino acids of 4.5 determined from the
total nitrogen content and the amino nitrogen content was charged
and the pH was adjusted to 9.5 by addition of 25% aqueous sodium
hydroxide.
[0143] The resulting solution was warmed to 50.degree. C. To the
warmed solution, 3-glycidoxypropyltriethoxysilane 14 g (0.05 mol,
equimolar amounts of the amino nitrogen content of the hydrolyzed
pea protein) was added dropwise over about 1 hour with stirring.
After completion of the dropwise addition, stirring was continued
for 14 hours at 50.degree. C. Thereafter, 17% aqueous hydrochloric
acid was added to adjust to pH6.0 and 133 g of an aqueous solution
of N-[2-hydroxy-3-(3'-trihydroxysilyl)propoxy]propyl]hydrolyzed pea
protein (silylated hydrolyzed pea protein) having the solid
concentration of 26.2% was obtained.
[0144] The extent of the reaction calculated based on the amino
nitrogen contents before and after the reaction was 83%. As the
result, moles of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl]hydrolyzed pea
protein was calculated and determined to be 0.04.
[0145] Next, the aqueous solution of the silylated hydrolyzed pea
protein, thus prepared, was charged into a 2 liter glass lid
circular reactor. Then, 157 g of water was added to adjust the
solid concentration to 12%, and 17% aqueous hydrochloric acid was
added to adjust to pH2.2.
[0146] The resulting solution was warmed to 50.degree. C. and to
the solution, a mixture of methyltriethoxysilane 37.4 g (0.21 mol)
and phenyltriethoxysilane 10 g (0.04 mol) was added dropwise with
stirring over about 30 minutes. After the completion of the
dropwise addition, stirring was continued for 4 hours at 50.degree.
C.
[0147] Then, an aqueous sodium hydroxide was added dropwise to
adjust pH of the solution to 6.0, and thereto, dimethyl
polysiloxane [KF-96A-1000cs (trade name) manufactured by Shin-Etsu
Chemical Co., Ltd.] 559 g was added dropwise over 2.5 hours with
stirring at 600 rpm. Thereafter, the solution was stirred at 10,000
rpm using a homomixer at 50.degree. C., and finely emulsified.
[0148] Next, for the surface treatment of capsule wall,
trimethylchlorosilane 11.7 g was added to the resulting emulsion
with stirring at 400 rpm, 50.degree. C., pH was adjusted to 6.0
with 5% aqueous sodium hydroxide, and the resulting reaction
solution was heated to reflux. After distilling off the vapor
containing alcohol, the reflux was further continued for 2 hours
with stirring at 400 rpm.
[0149] The resulting reaction solution was slowly cooled to room
temperature with stirring at 100 rpm and solid concentration was
adjusted to 60% by adding water to obtain 1010 g of microcapsules
containing dimethylpolysiloxane and having capsule wall made of a
co-polycondensate of the silylated hydrolyzed pea protein,
methyltriethoxysilane and phenyltriethoxysilane.
Reference Example 3: Production of Microcapsules Having Capsule
Wall Made of a Co-Polycondensate of Silylated Hydrolyzed Wheat
Protein, Methyltriethoxy Silane and Octyltriethoxysilane and
Containing Squalane
[0150] Into a 1 liter beaker, 25% aqueous solution of wheat protein
hydrolyzate (hydrolysed wheat protein) 100 g (0.035 mol as moles
calculated from amino nitrogen content) having average
polymerization degree of amino acids of 7 determined from the total
nitrogen content and the amino nitrogen content was charged and pH
was adjusted to 9.5 by addition of 25% aqueous sodium
hydroxide.
[0151] The resulting solution was warmed to 50.degree. C. To the
warmed solution, 3-glycidoxypropyltriethoxysilane 9.5 g (0.035 mol,
equimolar amounts of the amino nitrogen content of the hydrolyzed
wheat protein) was added dropwise over about 1 hour with stirring.
After completion of the dropwise addition, stirring was continued
for 14 hours at 50.degree. C. Thereafter, 17% aqueous hydrochloric
acid was added to adjust to pH6.0 and 106 g of an aqueous solution
of N-[2-hydroxy-3-(3'-trihydroxysilyl)propoxy]propyl]hydrolyzed
wheat protein (silylated hydrolyzed wheat protein) having the solid
concentration of 24.3% was obtained.
[0152] The extent of the reaction calculated based on the amino
nitrogen contents before and after the reaction was 85%. As the
result, moles of
N-[2-hydroxy-3-[3'-(trihydroxysilyl)propoxy]propyl] hydrolyzed
wheat protein was calculated and determined to be 0.03.
[0153] Next, the aqueous solution of the silylated hydrolyzed wheat
protein, thus prepared, was charged into a 2 liter glass lid
circular reactor. Then, 109 g of water was added to adjust the
solid concentration to 12%, and 17% aqueous hydrochloric acid was
added to adjust to pH2.2.
[0154] The resulting solution was warmed to 50.degree. C. and to
the solution, a mixture of methyltriethoxysilane 12 g and
octyltriethoxysilane 3.7 g was added dropwise with stirring over
about 30 minutes. After the completion of the dropwise addition,
stirring was continued for 4 hours at 50.degree. C.
[0155] Then, an aqueous sodium hydroxide was added dropwise to
adjust pH of the solution to 6.0, and thereto, squalane 331 g was
added dropwise over 2.5 hours with stirring at 600 rpm, 50.degree.
C. Thereafter, the solution was stirred at 10,000 rpm using a
homomixer at 50.degree. C., and finely emulsified.
[0156] Next, for the surface treatment of capsule wall,
trimethylchlorosilane 1.9 g was added to the resulting emulsion
with stirring at 400 rpm, 50.degree. C., pH was adjusted to 6.0
with 5% aqueous sodium hydroxide, and the resulting reaction
solution was heated to reflux. After distilling off the vapor
containing alcohol, the reflux was further continued for 2 hours
with stirring at 400 rpm.
[0157] The resulting reaction solution was slowly cooled to room
temperature with stirring at 100 rpm and solid concentration was
adjusted to 60% by adding water to obtain 613 g of aqueous
dispersion of microcapsules containing squalane and having capsule
wall made of a co-polycondensate of the silylated hydrolyzed wheat
protein, methyltriethoxysilane and octyltriethoxysilane.
Reference Example 4: Production of Microcapsules Having Capsule
Wall Made of a Co-Polycondensate of Silylated Hydrolyzed Soy
Protein, Methyltriethoxy Silane and Octyltriethoxysilane and
Containing Water
[0158] Into a 1 liter beaker, 25% aqueous solution of soy protein
hydrolyzate (hydrolysed soy protein) 100 g (0.03 mol as moles
calculated from amino nitrogen content) having average
polymerization degree of amino acids of 5.5 determined from the
total nitrogen content and the amino nitrogen content was charged
and pH was adjusted to 9.5 by addition of 25% aqueous sodium
hydroxide.
[0159] The resulting solution was warmed to 50.degree. C. To the
warmed solution, 3-glycidoxypropyltriethoxysilane 7.5 g (0.03 mol,
equimolar amounts of the amino nitrogen content of hydrolyzed soy
protein) was added dropwise over about 1 hour with stirring and
stirring was continued for 14 hours at 50.degree. C. after
completion of the dropwise addition.
[0160] Thereafter, 17% aqueous hydrochloric acid was added to
adjust to pH6.0 and 110 g of an aqueous solution of
N-[2-hydroxy-3-(3'-dihydroxymethylsilyl)propoxy]propyl]hydrolyzed
soy protein (silylated hydrolyzed soy protein) having the solid
concentration of 24.5% was obtained. The extent of the reaction
calculated based on the amino nitrogen contents before and after
the reaction was 86%. As the result, moles of
N-[2-hydroxy-3-[3'-(dihydroxymethylsilyl)propoxy]propyl]hydrolyzed
soy protein was calculated and determined to be 0.03.
[0161] Next, the aqueous solution obtained above was charged into a
2 liter glass lid circular reactor, 24.7 g of water was added to
adjust the solid concentration to 20%, and 17% aqueous hydrochloric
acid was added to adjust to pH2.0.
[0162] The resulting solution was warmed to 50.degree. C. and to
the solution, a mixture of methyltriethoxysilane 21.4 g (0.12 mol)
and octyltriethoxysilane 66.2 g (0.24 mol) was added dropwise with
stirring over about 30 minutes. After the completion of the
dropwise addition, stirring was continued for 16 hours at
50.degree. C.
[0163] Then, the stirring speed was increased to 600 rpm,
caprylic/capric Triglyceride 214 g to be the continuous phase (the
outer phase the capsules disperse in) was added with stirring,
stirring was continued until the phases inverted, 20% aqueous
sodium hydroxide was added to adjust to pH6, and stirring was
further continued at 50.degree. C. for 3 hours at 600 rpm.
[0164] Next, a mixture of trimethylchlorosilane 3.3 g (0.03 mol)
and trimethylethoxysilane 7.1 g (0.26 mol) was added with stirring
at 600 rpm, 50.degree. C., and then stirring was continued for 16
hours at 600 rpm, 50.degree. C. To the resulting reaction solution,
5% aqueous sodium hydroxide was added dropwise to adjust pH of the
solution to 6. The stirring speed was decreased to 400 rpm and the
resulting reaction solution was gradually heated to 80.degree. C.
and kept under reflux for 2 hours to remove generated alcohol and
water present in the continuous phase. Then, with stirring at 400
rpm, the temperature of the reaction solution was lowered to room
temperature, and 410 g of dispersion of microcapsules with about
50% water content in caprylic/capric Triglyceride was obtained
(calculated content of the capsules is 50%).
[0165] Analysis methods (test methods) will be described below
which were used for evaluation of the microcapsules produced in
Examples 1-12 and Reference examples 1-4 during and after their
manufacturing process.
Analysis Method 1: Solid Concentration
[0166] About 10 g of the obtained dispersion of microcapsules was
weighed accurately, and water content in the dispersion of the
microcapsules containing core material was measured with infrared
type water content meter LIBROR EB-280MOC (trade name) manufactured
by Shimadzu Corp. From the results, mass of the non-aqueous portion
of the obtained microcapsule dispersion [microcapsules containing
core material+free core material (core material not incorporated in
capsules)+ash] is determined.
[0167] That is, in the case of oil-in-water capsules, the weight of
the microcapsule dispersion is the mass of "water+microcapsule
containing core material+free core material+ash", and therefore,
the mass of the nonaqueous portion can be determined by the
measurement of water content.
Analysis Method 2: Ash Content
[0168] With ICP emission spectrophotometer SPS1700HVR (trade name)
manufactured by Seiko Denshi Kogyo Co., Ltd., concentration of Na
in the produced microcapsule dispersion was measured, and mass of
NaCl in the dispersion was calculated. It is considered that most
of the ash other than silica is NaCl, and, therefore, the NaCl
amount is used as ash content for estimating the core weight
ratio.
Analysis Method 3: Core Material Amount (Total Amount)
[0169] When the core material is an oily substance, 0.1 g of
obtained dispersion of microcapsules containing the core material
was weighed accurately, and thereto, 5 mol/L aqueous sodium
hydroxide 5 mL was added. The resulting dispersion was stirred at
50.degree. C. over 1 hour to destroy the capsule wall. After
cooling to room temperature, the resultant was transferred to a 500
mL separatory funnel, while being washed with about 100 mL of
water, followed by shaking well after adding n-hexane 100 mL and
then allowed to stand still.
[0170] After the liquid phase separated into two layers, the
n-hexane layer was transferred into another container. This
operation was repeated three times, and the resulting n-hexane
layers were combined and concentrated to make the amount to exactly
100 mL. An aliquot of the n-hexane solution was analyzed by liquid
chromatography, and the core material amount contained in the
microcapsules and in the continuous layer of the dispersion (the
total amount of the core material) was determined from a
calibration curve constructed by using standard solutions prepared
separately.
Analysis Method 4-1: Amount of Free Core Material
[0171] When the core material is an oily substance, 1 g of obtained
dispersion of microcapsules containing core material was weighed
accurately, and the dispersion was transferred to a 500 mL
separatory funnel, while being washed with about 100 mL of water,
followed by shaking well with adding n-hexane 100 mL and then
allowed to stand still. After the liquid phase separated into two
layers, the n-hexane layer was transferred into another container.
This operation was repeated three times, and the resulting n-hexane
layers were combined and concentrated to make the amount to exactly
100 mL. An aliquot of the n-hexane solution was analyzed by liquid
chromatography, and the core material amount present in the
continuous layer of the obtained dispersion, that was the amount of
the core material which was not contained into capsules (amount of
free core material) was determined from a calibration curve
constructed by using standard solutions prepared separately. In
this specification, the amount of free core material was
represented as a percentage of the amount of free core material in
the total amount of the dispersion including the microcapsules.
Analysis Method 4-2: Leaching Rate of Core Material
[0172] The increase of the amount of the free core material in a
period can be measured by measuring the amount of the free core
material again after a certain period (e.g. after 1 day, after 1
month), and leaching rate of core material can be determined by the
following numerical formula. In Examples and Comparative Examples,
increase of percentage value in 30 days (%/month) was calculated
and shown as the leaching rate of core material.
[ Numerical formula 1 ] ##EQU00001## Leaching Rate = ( Measured
value after a certain period of time ) - ( Measured value
immediately after preparation ) Elapsed time ##EQU00001.2##
[0173] From analysis of the Analysis 1-3 above, it is possible to
determine the core weight ratio by the following numerical
formula.
[ Numerical formula 2 ] ##EQU00002## Core weight ratio ( % ) = (
Measured value in Analysis method 2 ) - ( Measured value in
Analysis method 3 ) ( Measured value in Analysis method 1 ) - (
Measured value in Analysis method 2 ) - ( Measured value in
Analysis method 3 ) .times. 100 ##EQU00002.2##
Analysis Method 5: Particle Size Distribution of Capsules
[0174] Particle size distribution of capsules was measured by using
SALD-2000 (trade name) manufactured by Shimadzu Corp. In this
analyzer, the average particle size diameter and the standard
deviation of the particle size distribution were shown. Small
standard deviation means narrow distribution width of particle
size.
Analysis 6: Microscopic Observation
[0175] Spherical state and particle diameter of the capsules were
observed by JSM-6010LA type electron microscope manufactured by
JEOL Ltd. Further, in the manufacturing process of capsules,
whether the capsules were formed or not was determined by optical
microscopy observation (100-1000 fold).
[0176] Based on the above analysis results, the obtained
microcapsules in Examples 1-12 and those in Reference Examples 1-4
were compared, and the results are shown in Table 1. In the Table,
"free amount" is the amount of free core material, and "leaching
rate" is the rate of leaching of core material. Since the contained
material of the microcapsules of Example 12 and Reference Example 4
was water, it was not possible to analyze the free amount and the
rate of leaching of the core material. The core weight ratios of
Example 12 and Reference Example 4 are estimated values obtained by
calculation, and they are appended mark * in the Table.
TABLE-US-00001 TABLE 1 Particle size distribution (Volume
distribution) Average Core particle weight Free Leaching size
diameter Standard ratio amount rate Microcapsule (.mu.m) deviation
(%) (%) (%/M) Product of 1.553 0.227 90.1 0.000 0.095 Example 1
Product of 2.276 0.174 89.7 0.000 0.352 Example 2 Product of 1.557
0.133 89.9 0.048 0.034 Example 3 Product of 1.877 0.160 87.8 0.123
0.065 Example 4 Product of 2.498 0.176 87.8 0.029 0.052 Example 5
Product of 2.379 0.225 89.8 0.000 0.137 Example 6 Product of 2.563
0.235 89.8 0.000 0.371 Example 7 Product of 1.464 0.196 89.9 0.012
0.043 Example 8 Product of 2.781 0.201 88.4 0.571 0.403 Example 9
Product of 2.484 0.196 88.5 0.374 0.367 Example 10 Product of 2.988
0.238 89.0 0.963 0.387 Example 11 Product of 0.554 0.120 48.5* --
-- Example 12 Product of 3.246 0.245 88.3 3.871 0.870 Reference
Example 1 Product of 3.133 0.302 87.9 3.888 0.970 Reference Example
2 Product of 4.091 0.335 88.8 4.212 0.914 Reference Example 3
Product of 0.643 0.132 51.5* -- -- Reference Example 4
[0177] As shown in Table 1, microcapsules having capsule wall made
of a co-polycondensate of silylated amino acid and silane compound
produced in Examples 1-11 show smaller standard deviations in the
particle size distribution compared to microcapsules having capsule
wall made of a co-polycondensate of silylated peptide and silane
compound produced in Reference Examples 1, 2 and 3.
[0178] As for the capsules containing water, a smaller standard
deviation in the particle size distribution is shown in Example 12
than in Reference Example 4. That is, in Examples 1-12,
microcapsules having narrow particle size distribution width were
produced.
[0179] Further, the amounts of free core material and leaching
rates of core material of the microcapsules containing oily
substances produced in Examples 1-11 were smaller than those of the
microcapsules containing oily substances produced in Reference
Examples 1-3.
[0180] From this result, it is obvious that microcapsules having
capsule wall made of a co-polycondensate of silylated amino acid
and silane compound produced in Examples 1-11 are better in core
material uptake and cause much less leaching of the core material,
probably due to dense capsule wall, compared to microcapsules
having capsule wall made of a co-polycondensate of silylated
peptide and silane compound produced in Reference Examples 1-3.
[0181] Regarding microcapsules containing oily substances produced
in Examples 1-11, pH stability and stability in the presence of a
cationic substance were examined and odor was evaluated sensory.
Evaluation methods and evaluation criteria are shown below. As
comparative products, microcapsules having capsule wall made of a
co-polycondensate of silylated peptide and silane compound produced
in Reference Example 1-3 were used.
[PH Stability Test]
[0182] Aqueous dispersions of microcapsules having the solid
concentration of 60 mass % were diluted 10-fold with water, and pH
were adjusted to 3, 4 and 5 with aqueous hydrochloric acid of 1
mass % concentration. The resulting solutions were allowed to stand
for 2 days at room temperature, and the solution states after 2-day
standing were visually observed and evaluated on the following
evaluation criteria. The results are shown with the evaluation
results of stability in the presence of a cationic substance and
odor in Table 2.
Evaluation Criteria of PH Stability
[0183] Capsules sedimentate and aqueous phase is separated on upper
part of the dispersion: +++
[0184] Capsules sedimentate a little and small amount of aqueous
phase is separated: ++
[0185] Capsules sedimentate somewhat but aqueous phase is not
separated: +
[0186] No change and same as before pH adjustment: -
[Stability Test in the Presence of a Cationic Substance]
(Compatibility with Cationic Substance)
[0187] An aqueous dispersion of the microcapsules having a solid
concentration of 60 mass % was diluted 10-fold with water. To 10 g
of the 10-fold diluted dispersion, 0.5 g of a mixture of stearyl
trimethylammoniumchloride, water and isopropanol at mass ratio of
25: 69: 6 [Catinal STC-25W (trade name); Kao Corporation Ltd.] was
added. The resulting solution was stirred well, and allowed to
stand at room temperature for 2 days. The solution state after
2-day standing was visually observed and evaluated on the following
evaluation criteria.
Evaluation Criteria of Stability in the Presence of a cationic
substance
[0188] Capsules sedimentate and aqueous phase is separated on upper
part of the dispersion: +++
[0189] Capsules sedimentate a little but aqueous phase is not
separated: ++
[0190] Capsules sedimentate somewhat but aqueous phase is not
separated: +
[0191] No change and same as before mixing: -
[Evaluation of Odor of Microcapsule Dispersion]
[0192] An aqueous dispersion of the microcapsules having a solid
concentration of 60 mass % was diluted 2-fold with water, and
warmed to 40.degree. C. The odor was evaluated on the following
evaluation criteria by 10 panelists, and the average of the ten was
calculated as the evaluation value of odor.
Evaluation Criteria of Odor
[0193] Odor is not at all care about: 3
[0194] Odor is not care about: 2
[0195] Odor is somewhat bothersome (Feel somewhat): 1
[0196] Odor is very bothersome (Feel strongly): 0
TABLE-US-00002 TABLE 2 Compatibility pH stability with cationic
Evaluation Microcapsule 3 4 5 substance of Odor Product of - - - -
2.5 Example 1 Product of - - - - 2.4 Example 2 Product of ++ - - ++
2.5 Example 3 Product of + - - ++ 2.5 Example 4 Product of + + - -
2.3 Example 5 Product of + + - - 2.4 Example 6 Product of - - - -
2.3 Example 7 Product of + - - + 2.3 Example 8 Product of - - - -
2.0 Example 9 Product of - - - - 2.1 Example 10 Product of ++ - -
++ 2.4 Example 11 Product of ++ + - + 1.2 Reference Example 1
Product of ++ + - ++ 0.3 Reference Example 2 Product of +++ ++ +
+++ 0.2 Reference Example 3
[0197] Regarding the stability in acidic pH, [0198] all of
microcapsules of Examples had no problem in pH5 or higher, [0199]
microcapsules produced in Examples 5 and 6 became sediments a
little in pH 4 and [0200] microcapsules produced in Examples 3 and
11 were aggregated and sedimented and microcapsules produced in
Examples 4, 5, 6 and 8 sedimented somewhat in pH 3.
[0201] In contrast, microcapsules of Reference examples 1-3
aggregated and were in an almost unusable state in pH4 or lower.
Thus, it is evident that the microcapsules of Examples have higher
stability at acidic pH.
[0202] In Examples 3, 4, 8 and 11, a silylated acidic amino acid
was used, in Examples 5 and 6, a silylated basic amino acid was
used, and in these Examples, the produced microcapsules were
slightly poor in pH stability. Microcapsules produced by using a
silylated acidic amino acid or a silylated basic amino acid seemed
to be somewhat vulnerable to pH change compared with microcapsules
produced by using a silylated neutral amino acid. Therefore, it is
contemplated that, in a formulation where low pH is required, high
stability can be achieved by using microcapsules having capsule
wall made of a co-polycondensate of silylated neutral amino acid
and silane compound.
[0203] The test results regarding compatibility with the cationic
substance showed that, among the microcapsules produced in Examples
1-11, microcapsules produced in Examples 3, 4, 8 and 11 where an
acidic amino acid, aspartic acid or glutamic acid, was utilized for
the silylated amino acid, are somewhat poor in compatibility with
the cationic substance, but the other products in the Examples are
stable without causing turbidity or precipitation by associating
with the cationic substance.
[0204] On the contrary, the microcapsules produced in Reference
Examples 1-3 by using silylated peptides, caused vigorous
aggregation with the cationic substance and sedimentation of the
microcapsules occurred.
[0205] Regarding odor of microcapsule dispersion, evaluation values
of the microcapsules produced in Examples 1-11 were values of 2 or
more, while lower evaluation values were given to the micro
capsules produced in Reference Examples 1-3 using silylated
peptides. Thus, it was considered that the use of the microcapsules
produced in Reference Examples 1-3 in cosmetics may be
restricted.
[0206] Next, examples of cosmetics will be shown. In the tables
showing the formulations of Examples and Comparative Examples, the
amount of each component is represented by part by mass and, when
amount of a component is not net solid content, solid concentration
of the component is shown in parentheses after the component
name.
Example 13 and Comparative Examples 1-2
[0207] The sunscreen cream of the composition shown in Table 3 was
prepared to measure SPF and the feeling of use was evaluated. In
Example 13, the aqueous dispersion of microcapsules having capsule
wall made of a co-polycondensate of silylated serine and methyl
triethoxysilane and containing 2-ethylhexyl p-methoxycinnamate as
ultraviolet absorber, prepared in Example 1, was used, and [0208]
in Comparative example 1, the aqueous dispersion of microcapsules
having capsule wall made of a co-polycondensate of silylated
hydrolyzed casein and methyl triethoxysilane and containing
2-ethylhexyl p-methoxycinnamate, prepared in Reference Example 1,
was used.
[0209] Further, in Comparative Example 2, 2-ethylhexyl
p-methoxycinnamate was used as ultraviolet absorber, in place of
microcapsules containing the ultraviolet absorber, and in
combination with polyoxyethylene (20) oleyl ether for
emulsification of the ultraviolet absorber. In the table,
methyltriethoxysilane is referred to as silane compound.
TABLE-US-00003 TABLE 3 Compar- Compar- Example ative ative 13
Example 1 Example 2 Aqueous dispersion of microcapsules 20.0 0.0
0.0 having capsule wall made of a copolycondensate of silylated
serine and silane compound and con- taining a UV absorber, prepared
in Example 1 (60%) Aqueous dispersion of microcapsules 0.0 20.0 0.0
having capsule wall made of a copolycondensate of silylated
hydrolyzed casein and silane com- pound and containing a UV
absorber, prepared in Reference Example 1 (60%) 2-Ethylhexyl
p-methoxycinnamate 0.0 0.0 10.8 Polyoxyethylene (20) oleyl ether
0.0 0.0 2.5 Isononyl isononanoate 6.0 6.0 6.0 Self-emulsifying type
glyceryl 2.0 2.0 2.0 stearate Cetearyl alcohol 2.0 2.0 2.0 Sorbitan
stearate 1.0 1.0 1.0 Xanthan gum 0.2 0.2 0.2 Mixture of Sodium
acrylate/sodium 1.0 1.0 1.0 acryloyl dimethyltaurine copolymer,
Isohexadecane, Polysorbate80 and Water *1 1, 3-Butylene glycol 2.0
2.0 2.0 Mixture of Paraoxybenzoic acid 0.2 0.2 0.2 esters,
Ethoxydiglycol and Phenoxyethanol *2 Purified water Amount Amount
Amount making making making a total a total a total of 100 of 100
of 100 In Table 3, *1 is SIMULGEL EG (trade name) manufactured by
SEPPIC, and *2 is Seisept-H (trade name) manufactured by SEIWA
KASEI COMPANY, LIMITED
[0210] SPF value of the sunscreen cream was measured by SPF
analyzer Labsphere UV-20005 (trade name) manufactured by Labsphere,
Inc. Further, each of the sunscreen cream was applied on the skin,
and then smoothness and stickiness were evaluated on the following
evaluation criteria and odor was evaluated on the same evaluation
criteria as the criteria described in the above [Evaluation of odor
of microcapsule dispersion] by 10 panelists. These results are
shown in Table 4. The result of sensory evaluation is represented
as the average of ten evaluation values.
Evaluation Criteria of Smoothness
[0211] Very smooth: 2 [0212] Slightly smooth: 1 [0213] Grainy:
0
Evaluation Criteria of Stickiness
[0213] [0214] No sticky feeling: 2 [0215] Slightly sticky: 1 [0216]
Very sticky: 0
TABLE-US-00004 [0216] TABLE 4 Compar- Compar- Example ative ative
13 Example 1 Example 2 SPF value 29 21 22 Smoothness after 1.8 1.7
1.0 application Stickiness 1.7 1.0 0.3 Odor 2.5 1.2 0.2
[0217] As shown in Table 4, the sunscreen cream of Example 13 with
which microcapsules having capsule wall made of a co-polycondensate
of silylated serine and silane compound and containing 2-ethylhexyl
p-methoxycinnamate blended, showed higher SPF value than the
sunscreen cream of Comparative example 1 blended with micro
capsules having capsule wall made of a co-polycondensate of
silylated hydrolyzed casein and silane compound and containing
2-ethylhexyl p-methoxycinnamate and the sunscreen cream of
Comparative example 2 blended with the ultraviolet absorber without
encapsulation.
[0218] Regarding the feeling of use, the sunscreen cream of
Examples 13, where the ultraviolet absorber was encapsulated by
capsule wall made of the .alpha. co-polycondensate of silylated
amino acid and silane compound, was evaluated as excellent in
smoothness, less stickiness and less odor, as compared with the
sunscreen cream of Comparative Example 2, where the ultraviolet
absorber was not encapsulated. In comparison with the sunscreen
cream of Comparative Example 1, where the ultraviolet absorber was
encapsulated by capsule wall made of a co-polycondensate of
silylated peptide and silane compound, almost the same result of
the evaluation was obtained in smoothness but excellent result was
obtained in stickiness. This result shows that the hydrolyzed
protein constituting the capsule wall is easier to cause stickiness
than amino acid.
Example 14 and Comparative Examples 3-4
[0219] Milky lotions having the composition shown in Table 5 were
prepared and stickiness during use, spreadability and smoothness
were evaluated. In Example 14, the aqueous dispersion of
microcapsule having capsule wall made of a co-polycondensate of
silylated glycine, methyltriethoxysilane and phenyltriethoxy silane
and containing dimethylpolysiloxane, prepared in Example 9, was
used, [0220] in Comparative example 3, the aqueous dispersion of
microcapsules having capsule wall made of a co-polycondensate of
silylated hydrolyzed pea protein, methyltriethoxysilane and
phenyltriethoxysilane and containing dimethylpolysiloxane, prepared
in Reference Example 2, was used, and [0221] in Comparative Example
4, dimethylpolysiloxan was used as it is, in place of the
microcapsules containing dimethylpolysiloxan.
TABLE-US-00005 [0221] TABLE 5 Compar- Compar- Example ative ative
14 Example 3 Example 4 Aqueous dispersion of microcapsules 15.0 0.0
0.0 having capsule wall made of a copolycondensate of silylated
glycine and silane compound, and containing dimethylpolysiloxane,
prepared in Example 9 (60%) Aqueous dispersion of 0.0 15.0 0.0
microcapsules having capsule wall made of a copolycondensate of
silylated hydrolyzed pea protein and silane compound, and
containing dimethylpolysiloxane, prepared in Reference example 2
(60%) Dimethylpolysiloxane *3 0.0 0.0 8.1 Carboxyvinyl polymer 30.5
30.5 30.5 neutralized product (0.5%) 1. 3-Butylene glycol 5.0 5.0
5.0 Mixture of Paraoxybenzoic acid 0.2 0.2 0.2 esters,
Ethoxydiglycol and Phenoxyethanol *2 Purified water Amount Amount
Amount making making a making a a total total of total of of 100
100 100 In Table 5, *2 is Seisept-H (trade name) manufactured by
SEIWA KASEI COMPANY, LIMITED and *3 is KF-96A-1000cs (trade name)
manufactured by Shin-Etsu Chemical Co., Ltd.
[0222] The milky lotions of Example 14 and Comparative Examples 3
and 4 were evaluated by 10 panelists, picking up each of milky
lotion to their hands and applying the emulsions to their faces.
The spreadability of the lotions was evaluated on the following
evaluation criteria and stickiness and smoothness were evaluated on
the same evaluation criteria as those in Example 13. These results
are shown in Table 6, represented as the average value of ten.
Evaluation Criteria of Spreadability
[0223] Good spreadability: 2 [0224] Moderate spreadability: 1
[0225] Poor spreadability: 0
TABLE-US-00006 [0225] TABLE 6 Compar- Compar- Example ative ative
14 Example 3 Example 4 Spreadability 1.7 1.6 1.0 Stickiness 1.8 1.0
0.2 Smoothness 1.6 1.5 0.5
[0226] As shown in Table 6, the milky lotion of Example 14 was
better than that of Comparative Example 4 in spreadability,
stickiness and smoothness upon application to the skin. Thus, the
effect of encapsulating the oily substance was clearly confirmed.
Further, in comparison with the milky lotion of Comparative Example
3, although, there was no significant difference in evaluation
values for spreadability and smoothness, higher evaluation value of
stickiness was obtained. This result shows that the silylated
hydrolyzed protein constituting the capsule wall is easier to cause
stickiness than silylated amino acid.
Example 15 and Comparative Examples 5-6
[0227] The lotion of the composition shown in Table 7 was prepared
and affinity to skin and smoothness and stickiness after
application on skin were evaluated. In Example 15, the aqueous
dispersion of micro capsules having capsule wall made of a
co-polycondensate of silylated aspartic acid and methyl
triethoxysilane and containing squalane, prepared in Example 11,
was used and [0228] in Comparative example 5, the aqueous
dispersion of microcapsules having capsule wall made of a
co-polycondensate of silylated hydrolyzed wheat protein and
methyltriethoxysilane and containing squalane, prepared in
Reference example 3, was used.
[0229] Further, in Comparative Example 6, in place of the
microcapsules containing squalane, squalane was used as it is, in
combination with polyglyceryl monostearate as a surfactant for
emulsification of squalane.
TABLE-US-00007 TABLE 7 Compar- Compar- Example ative ative 15
Example 5 Example 6 Aqueous dispersion of micro- 1.00 0.00 0.00
capsules having capsule wall made of a copolycondensate of
silylated aspartic acid and methyl triethoxysilane and containing
squalane, prepared in Example 11 (60%) Aqueous dispersion of micro-
0.00 1.00 0.00 capsules having capsule wall made of a
copolycondensate of silylated hydrolyzed wheat protein and
methyltriethoxysilane and containing squalane, prepared in
Reference Example 3 (60%) Squalane 0.00 0.00 0.54 Polyglyceryl
monostearate 0.00 0.00 1.00 1,3-Butylene glycol 6.00 6.00 6.00
Glycerin 5.00 5.00 5.00 Polyethyleneglycol 4000 3.00 3.00 3.00
Ethanol 7.00 7.00 7.00 Mixture of Paraoxybenzoic acid 2.00 2.00
2.00 esters, Ethoxydiglycol and Phenoxyethanol *2 Purified water
Amount Amount Amount making making making a total a total a total
of 100 of 100 of 100
[0230] Each of the lotions of Example 15 and Comparative Examples
5-6 was applied to face, and, spreadability on skin, stickiness and
smoothness upon application were evaluated by 10 panelists
according to the same criteria as in Example 13. In addition,
affinity to skin upon application was evaluated according to the
following evaluation criteria. The results are shown as the average
value of the ten in Table 8.
Evaluation Criteria of Affinity to Skin
[0231] Good affinity: 2 [0232] Moderate affinity: 1 [0233] Poor
affinity: 0
TABLE-US-00008 [0233] TABLE 8 Compar- Compar- Example ative ative
15 Example 5 Example 6 Affinity to skin 1.8 1.0 0.3 Smoothness
after 1.7 1.3 0.4 application Stickiness 1.5 1.2 0.2
[0234] As is apparent from the results shown in Table 8, the lotion
of Example 15, in which the microcapsules having capsule wall made
of a co-polycondensate of silylated aspartic acid and
methyltriethoxysilane and containing squalane were blended, was
confirmed to be better in smoothness and less stickiness, compared
not only to the lotion of Comparative example 6 where squalane was
not encapsulated, but also to the lotion of Comparative Example 5,
in which the microcapsules having capsule wall made of a
co-polycondensate of silylated hydrolyzed wheat protein and
methyltriethoxysilane containing squalane were blended.
Example 16 and Comparative Examples 7-8
[0235] A lipstick having the composition shown in Table 9 was
prepared and appearance, moisture content, smoothness upon
application and moist feeling after application were evaluated. In
Example 16, 50% caprylic/capric Triglyceride dispersion of
microcapsules containing water prepared in Example 12 was used, and
in Comparative Example 7, 50% caprylic/capric Triglyceride
dispersion of microcapsules containing water prepared in Reference
example 4 was used. Further, in Comparative Example 8,
caprylic/capric Triglyceride and purified water was used so as to
contain the same amount of water as the amount in Example 16. The
amounts of water contained in the microcapsules of Example 12 as
well as in the microcapsules of Reference example 4 were estimated
by calculation to be 48.5% and 51.0%, respectively, as shown in
Table 1, but the values were regarded as equivalent to 50%.
TABLE-US-00009 TABLE 9 Compar- Compar- Example ative ative 16
Example 7 Example 8 Caprylic/capric Triglyceride 9.26 0.00 0.00
dispersion of microcapsules containing water prepared in Example 12
(50%) Caprylic/capric Triglyceride 0.00 9.26 0.00 dispersion of
microcapsules containing water prepared in Reference Example 4
(50%) Purified water 0.00 2.50 2.50 (Hydrogenated
rosin/diisostearic 60.00 60.00 60.00 acid) glyceryl Candelilla row
4.00 4.00 4.00 Carnauba wax 3.00 3.00 3.00 Hydrogenated palm oil
3.00 3.00 3.00 Ozokerite wax 3.00 3.00 3.00 Beeswax 2.00 2.00 2.00
Cholesteryl hydroxystearate 2.00 2.00 2.00 Titanium oxide 2.00 2.00
2.00 Isostearoyl hydrolyzed silk*4 1.00 1.00 1.00 Lanolin alcohol
1.00 1.00 1.00 Diisostearyl malate 1.00 1.00 1.00 Mica 1.00 1.00
1.00 Alumina 0.50 0.50 0.50 Butyl hydroxy toluene 0.05 0.05 0.05
Tocopherol acetate 0.05 0.05 0.05 Red No. 201 1.50 1.50 1.50 Red
No. 202 1.50 1.50 1.50 Blue No. 1 0.10 0.10 0.10 Yellow No. 1 2.00
2.00 2.00 Caprylic/capric Triglyceride 1.30 1.30 8.80 In Table 9,
*4 is Promois EF-118D (trade name) manufactured by SEIWA KASEI
COMPANY, LIMITED.
[0236] The preparation of lipstick was carried out by mixing the
components in the Table and heating at 80.degree. C., followed by
defoaming and standing still. Water was separated at the bottom in
Comparative Example 8 on standing. On the other hand, in Example 16
and Comparative Example 7, homogeneity was maintained and such a
phenomenon was not observed. Then, each resultant mixture as it is
in Example 16 or Comparative Example 7 or the upper phase of the
mixture excluding water phase in Comparative Example 8 was poured
into a lipstick mold, followed by cooling to room temperature, and
taken out from the mold to obtain a lipstick.
[0237] Water content of the obtained lipsticks of Example 16 and
Comparative Examples 7-8 was measured with a Karl Fischer moisture
meter. In addition, the lipsticks of Example 16 and Comparative
Examples 7-8 were applied on the back of the hands of 10 panelists
in an appropriate amount, and smoothness during application was
evaluated according to the same evaluation criteria as in Example
13. Furthermore, moist feeling after application was evaluated
according to the following evaluation criteria. These results are
shown in Table 10, where smoothness and moist feeling are shown as
average value of the ten panelists.
Evaluation Criteria of Moist Feeling
[0238] Good moist feeling: 2 [0239] Moderate moist feeling: 1
[0240] Poor moist feeling: 0
TABLE-US-00010 [0240] TABLE 10 Compar- Compar- Example ative ative
16 Example 7 Example 8 Water content 4.88 4.82 0.05 in lipstick (%)
Smoothness during 1.8 0.7 0.8 application Moist feeling 1.8 1.6 0.5
after application
[0241] As shown in Table 10, water contents of the lipstick of
Example 16 and Comparative Example 7 were 4.88% and 4.82%,
respectively, while the water content of the lipstick of
Comparative Example 8 was 0.05%. From these results, it was
apparent that higher water content in lipsticks can be achieved by
blending the microcapsules containing water.
[0242] Regarding smoothness during application, while the lipstick
of Example 16 was evaluated as very smooth, evaluation values of
Comparative Examples 7 and 8 were lower. In Comparative Example 7,
the microcapsules having capsule wall made of a co-polycondensate
of silylated peptide and silane compound containing water was used,
of which particle size distribution was wider than that of the
microcapsules used in Example 16, and that may have caused
foreign-body sensation upon application.
[0243] As for the moist feeling after application, the lipstick of
Example 16 blended with the microcapsule dispersion containing
water had higher water content compared to the lipstick of
Comparative Example 8, and that clearly imparted moist feeling to
skin. Although the lipstick of Comparative Example 7 which used
microcapsules having capsule wall made of a co-polycondensate of
silylated peptide and silane compound and containing water was also
shown to give good moist feeing after application, it seemed that
the lipstick of Example 16 was superior to the lipstick of
Comparative example 7, when considered with the feeling during
application.
* * * * *